"Ashley is ready to play," manager Carlo Ancelotti told a news conference on Monday. "Yesterday he trained and we will monitor his progress again tonight but he is good to play."
Ancelotti also has Didier Drogba back in his Champions League attack after the striker missed the opening three games of the campaign through suspension.
European soccer's governing body UEFA banned Drogba for harassing referee Tom Henning Ovrebo after last season's semi-final defeat by Barcelona.
The Ivory Coast international is in line for his 50th Champions League appearance for Chelsea.
The Londoners, who top Group D with three wins from three games, would advance to the knockout round with victory over Atletico who have had a poor start to the season and replaced coach Abel Resino with Quique Sanchez Flores on October 23.
Sanchez Flores said wins on Tuesday and in Saturday's La Liga clash against city rivals Real could revive the club's season.
Atletico have just one win from nine domestic matches and are third from bottom in La Liga.
"It would give us a lifeline in both competitions and would also be positive for the players from a psychological perspective," Sanchez Flores said.
"But Chelsea are difficult opponents in every department and to beat them we'll have to be at 100 percent."
If Atletico get knocked out of the Champions League they would settle for a spot in the Europa League.
"We are ambitious and the Europa League would still be good," said Sanchez Flores.