The Wales winger played the final half hour of Wales's 3-0 World Cup qualification defeat at home to Serbia on Tuesday, his first competitive action since July, and trained with his Real team mates for the first time on Wednesday.
"I think everyone knows his pre-season was not normal but his physical condition is not bad," Ancelotti told a news conference.
"I don't know if he will start but he will play some of the match," the Italian added. "He is very excited and very motivated."
The 24-year-old had been tipped to start on the bench for tomorrow night’s game against Villarreal.
But following injuries to Marcelo and Fabio Coentrao, the world’s most expensive player could be forced into an emergency role in defence.
Bale said: “I’m just looking forward to getting on the pitch and wherever the manager puts me I’ll be giving 100 per cent.
“We have to wait until the match day to see whether I’m picked or not but hopefully I can get my fitness up straight away and get a place in the team.
“I feel good, I’ve been training last week with Wales I’ve had two good sessions today.
“I got half an hour to 40 minutes game time with Wales and I’m feeling good but obviously I’m a bit behind physically than everybody else but hopefully I can catch up as soon as possible.
“I went straight away on international duty which probably wasn’t the best but I’ve been back for the last two days now.”