Aston Villa's Ashley Young jumps over Chelsea's John Terry during their English Premier League match at Stamford Bridge in London on Sunday. Stefan Wermuth / Reuters

Chelsea manager Carlo Ancelotti will decide whether to make a centerback one of his primary January transfer targets when Alex returns to Stamford Bridge this week.

Alex is undergoing rehabilitation following knee surgery and is due back at the club after a trip to Brazil.

The Brazilian central defender is not expected to be fit until the end of January, and Ancelotti wants to check the progress of his recovery before making a move in the transfer market.

In Alex's absence, Chelsea has looked unconvincing defensively and, with Branislav Ivanovic also missing while serving a one-match suspension, Ancelotti was forced to hand a league debut to teenager Jeffrey Bruma in the 3-3 draw with Aston Villa on Sunday.

Ancelotti conceded the absence of the more experienced centerbacks contributed to his side's failure to claim victory and blamed a lapse in concentration for Villa's added time equalizer that came two minutes after John Terry thought he had sealed a home win.

Ancelotti has been linked with a move for Benfica's David Luiz and Bolton's Gary Cahill, but he said: "We need to see the position of Alex. He comes back from Brazil. I don't like to speak here about which players but we need some players."

Chelsea had forced a 21st-minute lead through Frank Lampard's penalty but Villa fought back with a Ashley Young spot-kick and Emile Heskey's header.

Didier Drogba brought Chelsea back level before Terry fired home only for Ciaran Clark to claim a share of the points for the visitors.

"Defensively we lost something, obviously," Ancelotti said. "I want to say Bruma played very well but without Alex and Ivanovic we lost some energy on the high balls.

"We conceded the second goal for this reason. We needed to have more concentration in the box for the third goal."

The draw meant Chelsea failed to build on the midweek win over Bolton and left the Blues six point behind league leader Manchester United, which has played a game less.

Ancelotti, though, insists his side is still in the thick of the title race but acknowledges it must beat United when Sir Alex Ferguson's side visits Stamford Bridge on March 1 to regain the championship.

"First, they have to win (the game in hand)," Ancelotti said. "Second, I think the gap is not a wide gap. We have to beat them here and then we can say something about the title.

"It's not over because we are improving and I think we can say something again this season."

Villa manager Gerard Houllier insisted his side's performance showed it is capable of moving back up the table and drew a line under claims of unrest between the boss and certain players.

Defender Richard Dunne returned to the side for the first time since a training ground fall-out with assistant manager Gary McAllister, while midfielder Stephen Ireland could feature against Sunderland this week.

"Sometimes a player who is not playing obviously calls his agent who obviously calls the press," Houllier said. "But you can't play a game like that and get a result like that without having togetherness.

"This can be a turning point. We have lost so many points in the final minutes of games or after leading. This time a late goal got us a point.

"We have more experienced players back and they are coming back towards their usual level of match fitness."