The UEFA Champions League title-holders need to keep winning to try and remain in the hunt for what would be their second Spanish top flight title since 2008.
The 2011-12 La Liga champions were well held by Rayo at the Estadio del Rayo Vallecano on Sunday, before second-half goals five minutes apart from Cristiano Ronaldo and James Rodriguez made the difference.
"We decided to make pressure higher in the pitch at half time," the Italian told a media conference.
"We did in the first half but not as much as I wished. The performance in the second half was great. We have played very well and I think the victory is deserved.
"I am so happy. I am really satisfied for the second half. We showed great attitude and we played great. Physically we were good too, fighting a lot and performing good. I don't ask for anything else."
"Each game is different and each game has its different line-up," he said.
"James could help the team as he did in his first game after the injury. So, I decided to give a chance to James.
"Anyway, each game will be different in this period of time."
"Bale did pass the medical check this morning. I think he was fully recovered," Ancelotti said.
"Karim Benzema's substitution [for Isco in the 72nd minute] was due to wanting to bring on another midfielder and keep calm in terms of defensive game."
