Today's winner, two years after he won on Abetone...
Cefalù - Etna
Giro d'Italia - 9 May 2017
Giro d'Italia – Follow this cycling race live with Eurosport. The action starts at 20:05 on 9 May 2017. Our live coverage lets you follow all the key moments as they happen.
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And here's the top ten from today's stage - with all the big guns present and correct. Don't worry, Nairo Quintana was there, just outside the top ten...
Here's the moment Slovenia's Jan Polanc (UAE Team Emirates) won the stage on Mount Etna.
Confirmation that Bob Jungels is the new pink jersey after the Luxembourg national champion finished in the same time as Thomas, who trails the new maglia rosa by six seconds after those four bonus seconds for third.
Geraint Thomas wins the sprint for third place to take the final bonus seconds - but will it be enough for the Welshman to take the pink jersey? We'll have to see where Bob Jungels was in the ensuing pack...
Ilnur Zakarin finishes second, 19 seconds down on Polanc. With six bonus seconds for him, he'll cut his losses a bit.
Jan Polanc is going to hold on - he grapples with the final steep ramp towards the line, and then coasts on the downhill run to the line. Up goes the jersey and he starts punching the air. Victory for Jan Polanc!
Remember that Zakarin is 20 seconds down on his GC rivals after losing time in stage 2 with a late puncture. It looks like he should cut those loses.
Now Zakarin rides clear of the regrouped pack - and no-one goes with him. Polanc is approaching the flamme rouge and he has 45 seconds to play with. He should do it.
Hansen is reeled in just as Dumoulin, Pinot and Zakarin open up a sprint, with Yates and Thomas just there - Mollema too.
Another attack by Igor Anton of Dimension Data - but it's covered by Jesper Hansen, who refinds his mojo. The Astana rider opens up a small gap - but it won't be enough.
Nibali is joined by his rivals and they manage to reel in Hansen. All of the big guns appear to be there - and Polanc now has 1:05 to play with but still 2km left to ride. He's swinging all over the road, but may hold on...
ATTACK: Vincenzo Nibali darts out of the peloton! Sparking a reponse by his rivals...
Under the 3-to-go banner for Jan Polanc and he now has 1:20 over the pack. Nail-biting stuff. Hansen is not making too much headway, mind, so if someone else but Polanc wins, it may not be him.
Attack by Jesper Hansen of Astana - the young Danish climber is highly rated, and he's zipped off in pursuit of Polanc and the stage win that will commemorate the late Michele Scarponi.
It looks like Polanc will hold off, so we'll have two races - for the stage win, and for the pink jersey. Bob Jungels, who has 10 seconds over the others on GC, is still there in this main pack, albeit a bit further back.
Interestingly, Quintana has dropped back and onto the wheel of Nibali. Thomas, who is nearer the front, now has Movistar's Amador on his wheel. It looks like a big attack is about to come. Pinot is also on Nibali's wheel, while Kruijswijk is just ahead. Polanc now has 1:50.
Under the 5-to-go banner for lone leader Jan Polanc, who rode clear of his remaining escapee, Jacques Janse van Rensburg at the beginning of this 17.9km climb. Back with the pack it's Franco Pellizotti who sets a steady tempo for his team-mate Vincenzo Nibali, with another Bahrain Merida rider, Kanstantsin Siutsou just behind. Then we have Van Garderen, Thomas and Quintana leading the throng of GC favourites.
Attack by Igor Anton of Dimension Data - but it comes to nothing. The Spaniard is swept up just before Pierre Rolland is caught by the Hermans-led peloton. So, just Polanc ahead now. He has 2:10 over those who can deny him a second stage win on the Giro.
Slovenian Polanc has won nothing since he took his only previous professional win in the Giro two years ago. He's struggling and grimacing, but he could well hold on. He's 2:18 ahead of Rolland, who is now under 20 seconds ahead of the peloton.
Right, so Polanc now has 2:30 over Rolland, who himself has 30 second over the pack. It could still go either way, but you'd think Polanc may crack because he looks to be on the rivet. Rolland is now on the 12% segment.
Philip Deignan, who was pacing Geraint Thomas, has dropped back to help Mikel Landa. But the tactic has worked as the Sky duo rejoin the main pack of favourites. Meanwhile, Ben Hermans of BMC is now setting the tempo on the front for team-mate Tejay Van Garderen, who is in fourth wheel and seems to have got over his little wobble earlier.
Attack by Italian veteran Franco Pellizotti, the Bahrain Merida team-mate of Nibali. Nairo Quintana responds by sending Winner Anacona in pursuit, and Movistar managed to neutralise the move.
The rider forced to give Landa his wheel was Kenny Elissonde, which is another blow for Sky - they will be without one of their main climbers for the rest of this stage.
Puncture for Mikel Landa of Team Sky, who is forced to swap a front wheel with a team-mate. The Spaniard will have a tough chase back on now before the business end of this ascent.
Rolland has about 30 seconds on the pack but still trails Polanc by 3:10. Bilbao was caught by the pack - or will be, soon.
Confirmation from LottoNL-Jumbo that it was their leader Steven Kruijswijk who went down in that crash - but he's back in the pack after what must have been a big scare. That said, there are no yellow shirts near the front of the pack right now, so the Dutchman could be struggling.
ATTACK: Pierre Rolland (Cannondale-Drapac) rides clear from the pack. He has an Astana rider in pursuit. The Frenchman is already three minutes down on GC after losing time in Sardinia. It looks like Pello Bilbao from Astana in pursuit.
Here's that attack by Paolo Tiralongo - but, as expected, he's already been caught by the peloton. The pace is just too high for the 39-year-old, who always promised an attack on Etna in memory of his old team-mate and friend Michele Scarponi, who was killed a fortnight ago in a training exercise.
Jan Polanc is the lone leader for UAE Team Emirates and he has 3:45 to play with. He won a stage for Lampre-Merida two years ago - can he make it two? Meanwhile, Pavel Brutt is about to be caught by the pack.
Problems for Tejay Van Garderen: the American has a mechanical issue and then almost comes a cropped when he slows to stop. He's back on his way, but he could well have been involved in that earlier crash because he's looking a bit bashed up. Not a good day for BMC, who earlier saw Rohan Dennis withdraw.
Here's an overhead view of that big crash earlier... it looked nasty. Still awaiting confirmation who was involved.
Fernando Gaviria, the pink jersey, was one of the riders forced to take evasive action on that roundabout. He fought back into the pack, but he's already been dropped from the peloton. And here's our first attack from the pack, and it's local rider Paolo Tiralongo of Astana, the Italian veteran, who jumps early - too early, surely.
This is what the riders are now tackling - with that big red lava flow ramp of 12% half way up...
Ilnur Zakarin was one of the riders caught up in that crash, although it's not obvious whether or not the Katusha rider went down, or was held up when other team-mates went down. It looks like Steven Kruijswijk rode wide to avoid the turmoil after one of his LottoNL-Jumbo team-mates went down.
Meanwhile, the two leaders are onto the final climb - and Polanc has dropped Janse van Rensburg. He has four minutes to play with.
BIG CRASH: A handful or riders hit the deck on a roundabout - some of them pretty seriously. Riders from FDJ, LottoNL-Jumbo and Katusha are involved. So many of the pack overcooked the corner, many rode it out, others panicked and skidded and crashed. Chaos ahead of the final climb.
FLASHPOINT: Javier Moreno (Bahrain Merida) is caught on camera stretching over and pulling the jersey of Diego Rosa (Team Sky) on an uphill drag. Tensions clearly flying in the pack ahead of the final climb.
Polanc and Janse van Rensburg lead the stage having dropped two of their former fellow escapees. Alafaci has been caught and Brutt is in no-man's-land. The peloton rides at 4:55 with a gruppetto well and truly formed, including the likes of Greipel and Teklehaimanot. The relative calm before the storm.
That's it, Alafaci has been caught. The next rider could well be Brutt - the Russian seems to have been dropped by Janse Van Rensburg and Polanc. They're on an uncategorised climb ahead of the final ascent.
Eugenio Alafaci, who was part of the original break, has almost been caught by the pack. It's all Bahrain Merida now - although Gaviria still rides third wheel, doing the pink jersey justice. Andre Greipel is one of the big name riders to have been spat out the back.
The pack is really strung out now as Tuft continues the pace setting with numerous groups of riders trying to fight back on. The three leaders have 5:35 to play for and nothing is guaranteed - they may make it, or they may be caught if the pace really ramps up ahead of the final climb in 15km time.
When the peloton comes through that flagstone ramp zone many of them are forced to stop and unclip, such is the gradient. Oh, and there's a puncture for Alex Edmondson of Orica-Scott. Off the back of the pack, many riders have now been distanced - including the maglia azzurra, Daniel Teklehaimanot.
Once again it's Gaviria who leads the pack through the intermediate sprint - but perhaps he hasn't read the memo that dictates there are only points for the top three riders in intermediate sprints in this stage...
The break are grappling with a seriously steep cobbled ramp in the down of Biancavilla - it's almost as tough as the Koppenberg! The gap is still six minutes as birthday boy Svein Tuft comes to the front to help lead the chase for Orica-Scott team-mate Adam Yates.
Brutt takes maximum points in the second intermediate sprint - and with it three bonus seconds. Interestingly, that puts him six seconds clear now of Polanc on GC, so if they finish together and managed to hold off the peloton by a couple of minutes, then it will be the Russian who could take the maglia rosa - depending on bonus seconds at the finish.
There are four Sicilian riders in the peloton: Vincenzo Nibali (Bahrain Merida), Giovanni Visconti (also Bahrain Merida), Paolo Tiralongo (Astana) and Salvatore Puccio (Team Sky).
Nairo Quintana is off the back of the peloton being paced back by two Movistar team-mates. There looks to be no concern with the Colombian so perhaps it was a planned mechanical or a simple call of nature.
So, a reminder for those who have tuned in late. We had four riders out ahead but they are down to three after Eugenio Alafaci (Trek Segafredo) was dropped on a punchy ramp ahead of the intermediate sprint. So, the three leaders now are: Jan Polanc (UAE Team Emirates), Jacques Janse van Rensburg (Dimension Data) and Pavel Brutt (Gazprom-Rusvelo). They lead the Quick-Step and Bahrain Merida-led pack by 6:12. Alafaci is riding around 1:45 down on his former co-escapees.
Despite the uphill gradient, Fernando Gaviria edges clear of the pack to cross the intermediate sprint point in pole position. There are no points for fifth place but he's just enjoying his day out in pink. The gap is 6:05 for the four leaders. So, if Gaviria is going to lose the pink jersey today who will take over? And who will win the stage? Send me your thoughts on Twitter, @saddleblaze. I'll publish the best ones.
The first intermediate sprint is more like a climb: the moustachioed Alafaci is really struggling and is dropped by his fellow escapees as Brutt rides clear to take the maximum 8pts over the line. It will no doubt come back together as the riders thread their way through the town of Bronte.
The break is on the rolling roads between the two climbs and the gap has stabilised at six minutes. It's fair to say, the Sicilian scenery is fairly breaktaking...
Here's the aftermath of the Losada incident. We haven't heard whether or not the Spaniard has got back on his bike, but he didn't look in too good a shape, holding his collarbone as he was.
CRASH: Alberto Losada of Katusha-Alpecin is standing on the side of the road with his bike in the middle of it. He doesn't look too comfortable. It looks like his wheel got stuck in a grate crossing the road and it slammed him over the bars. The doctor is with him and there are many shakes of the head...
Alafaci is the first of the four escapees to pick up a musette as the break approaches the feed zone with a gap of 5:40. Over lunch, why not listen to Geraint Thomas's thoughts about today's finish on Mount Etna... someone should probably tell him the climb is going up the opposite side to that scaled in 2011, mind.
It's Canadian veteran Svein Tuft's 40th birthday today; he is currently 132nd in the overall standings and is one of the chief domestiques for Orica-Scott team-mate Adam Yates. This time three years ago Tuft took the maglia rosa after his GreenEdge team won the opening TTT in Belfast on his 37th birthday.
The descent happens in three sections with each split by a slight uphill segment. The leaders are already on the second downhill section but their gap is down to 5:55. It's worth adding that the road is very rolling in between the bottom of the descent and the start of the final climb, with at least four uncategorised lumps. Many rain capes and jackets have come on - it's still quite fresh out there at this altitude.
Daniel Teklehaimanot adds two points to his KOM tally to consolidate his lead in the maglia azzurra standings. The Eritrean leads the peloton over the summit 6:24 down on the pack and just ahead of Dimension Data team-mate Omar Fraile and then the pink jersey of Fernando Gaviria. We should add that it was Polanc who took third place and Brutt who took fourth, adding four points to his one solitary digit in the KOM standings. So, as it is, Teklahaimanot has 22 points, Janse Van Rensburg has 15 points and Fraile has 10 points - so we have three Dimension Data riders at the top of the mountains classification. You'd think it was a target, or something.
Here's the flashpoint between Janse van Rensburg and Polanc over the summit of that last climb.
But it's Janse van Rensburg who bounds clear in pursuit of the points to protect his team-mate Teklahaimanot's lead in the KOM standings. He pips Polanc over the summit before the Slovenian lays into him for apparently closing the door near the barriers. A bit harsh, that; the South African hadly wavered off his line. Unless the beef was about some agreement made earlier...
Pavel Brutt is driving the break through this wooded section near the summit of the climb. The gap has dropped ever so slightly to 7:17. There will be 15 points for the man who crests the summit first in 1km - and Brutt is already on the board in the KOM standings so expect him to be in the hunt.
The Bahrain Merida rider on the front - and ahead of the entire Quick-Step team - is Luka Pibernik of Slovenia, perhaps paving the way for his team-mate Vincenzo Nibali, the defending champion and local favourite. The gap comes down to 7:30 for the four leaders. For the fourth stage on the bounce the day's break contains a rider from Dimension Data - in today's case it's Jacques Janse van Rensburg.
Confirmation of that withdrawal from Rohan Dennis of BMC.
NEWSFLASH: Rohan Dennis of BMC has abandoned the Giro d'Italia. The Australian crashed heavily towards the end of stage three, losing more than five minutes. He was expected to continue in support of Tejay Van Garderen, and in pursuit of the two time trial stages, but he's clearly suffering from the neck injury he sustained in Sardinia.
With one-hundred clicks to go, this four-man break has 8:05 over the peloton and is combining well. Polanc, of UAE Team Emirates, sets the pace on this long but gentle climb. Back with the pack and Bahrain-Merida have sent a man onto the front - their leader Vincenzo Nibali is one of the favourites for today's stage.
The gap is now over eight minutes for the four escapees, who are on a little downhill segment that punctuates this long climb. The sun is out and the temperature warm - although the finish on Etna may be a little cloudy and fresh.
A reminder of the other jersey classification leaders: Andre Greipel is in the maglia cyclamino (points classification), Daniel Teklehaimanot is in the maglia azzurra (mountains classification) and Lukas Postlberger is in the maglia bianca (youth classification).
The gap is really growing for this four-man break: it's now pushing 7:30. Incidentally, Pavel Brutt is the virtual maglia rosa now - the Russian is currently in 92nd place on GC, 1:48 down on Gaviria. Interestingly, the next man on GC is his break-away companion Jan Polanc, a further three seconds back.
And here's Juan Antonio Flecha's recon ride up Mount Etna for you to feast your eyes upon before things hot up.
Today is all about the finish on Mount Etna. The last time the race came here, in 2011, Alberto Contador won the stage after a thrilling double ascent of the volcano - although he was later stripped of the win after his back-dated ban. Today's ascent is more difficult, though, with the riders using an alternative route up - one that features a lava-field ramp of 12% right in the middle.
The Quick-Step Floors team of race leader Fernando Gaviria are doing the pink jersey proud by setting the tempo on the front of the peloton, which trails the four leaders by 5:45. Of course, they have the Jungels card to play too - he could well be in Gaviria's maglia rosa today should he stay in touch with the big GC favourites.
We're now onto the first climb of the day, the Cat.2 Portella Femmina Morta, which is almost 33km long but has a gentle average gradient of around 5%. The break covered almost 47km in the first hour of racing, which goes to show that the pace is back up after the very slow start to the Giro in the opening two stages in Sardinia.
There was a minute's silence at the start of today's stage in memory of Wouter Weylandt, the Belgian rider who was killed six years ago to the day in a crash during the 2011 Giro d'Italia.
We join the stage LIVE now with the riders approaching the end of the opening 55km of flat. We have four riders out ahead: Eugenio Alafaci (Trek Segafredo), Jan Polanc (UAE Team Emirates), Jacques Janse van Rensburg (Dimension Data) and Pavel Brutt (Gazprom-Rusvelo). They have a lead of around 5 minutes having broken away shortly after the start.
All eyes were on double Giro winner and home favourite Vincenzo Nibali today at the start - and it's hardly surprising.
Today's 181km stage features a flat drag along the coast before the first of two climbs, the Cat.2 Portella Femmina Morta. After two intermediate sprints it's then the main course and the climb we've all been waiting for - the Cat.1 ascent of Mount Etna to the Rifugio Sapienza. Here's a video with more details...
Missed the three-day Grande Partenza of the Giro in Sardinia? Then read my recap of all the main talking points...
That man Gaviria is the third rider to wear the maglia rosa for the first time in his career since the start of the race, following stage 1 winner Lukas Postlberger and stage two winner Andre Greipel. The Colombian leads Germany's Greipel by 9 seconds on GC with Austria's Postlberger in third place at 13 seconds. The nearest of the big GC favourites is Bob Jungels, Gaviria's team-mate, who is in fourth place at 14 seconds - 10 seconds clear of the likes of Vincenzo Nibali, Nairo Quintana, Geraint Thomas et al. Needless to say, sprinter Gaviria won't be in pink this evening... but who will it be?
Before yesterday's rest day, on Sunday, Fernando Gaviria sprinted into the maglia rosa at the Giro d’Italia after his Quick-Step Floors team split the pack in strong crosswinds in an exciting finale to stage three in Cagliari.
Hello and welcome to live coverage of stage 4 of the Giro d'Italia - and it's the first summit (or as good as when that summit is a volcano) finish of this year's race, an explosive ride up Mont Etna.