Sinfield famously dedicated last year's Grand Final triumph to the critics who had dismissed his team's chances, and he senses a touch of deja vu as they prepare to take on Catalan Dragons in Perpignan in Friday's first preliminary semi-final.
"I think the team are ready for it," he said.
"A lot of people are writing us off again. Nobody expects us to go to France and win, so we go there without any pressure.
"I think they're a great side and we've struggled over there the last couple of years with the way they play at home in that stadium. It's very partisan and pretty fierce so we're expecting a really tough one and we need to be at our very best to win.
"But we've trained well this week. If we don't get this one right, we're finished for the year and we're not quite ready for it to end yet."
The Rhinos have suffered a major blow with the loss of prop Kylie Leuluai, who will sit out only his second match of the year after being handed a suspension for punching in last week's opening play-off win over Wakefield.
Former Wakefield and Huddersfield front rower Darrell Griffin is set to move into the starting line-up on his 250th career appearance, with the 6ft 6in Ian Kirke recalled to the bench after recovering from being knocked out in the last match of the regular season.
"We're swapping a small chunky guy for a big chunky guy but Kylie's a huge loss," said Sinfield.
"He's been outstanding for us this year. He's been a big rock in the centre of the field for us. I think he gets better with age and I'm delighted he's staying another year with us. He loves really physical games and they're always that against Catalan."