Cristiano Ronaldo returned to full training with Manchester United this morning and will return to the first team squad for the Champions League match against Villarreal tomorrow. The Portuguese forward has not played this season after undergoing ankle surgery after Euro 2008, but today played a full part in a session at United's Carrington training complex and will probably be on the bench for the group E match at Old Trafford, according to the United manager Sir Alex Ferguson. Ronaldo was expected to be out of action until October.

"He'll certainly be involved," Ferguson said today. "I have a decision to make over whether or not to start him, but it's most likely he'll be a sub."

It will also be Ronaldo's first appearance for United since the summer's protracted transfer saga during which he expressed a desire to play for Real Madrid and seemed likely to leave the Premier League champions for La Liga. After United blocked the move, Ronaldo restated his commitment to the club and claimed this week that he is unconcerned by any potential backlash from the supporters.

"When I put on that shirt, I give my all," Ronaldo said. "I am already in the history of the club. When I play again, the fans will love me again."

United have endured a poor start to the season in Ronaldo's absence, scoring only three times in their first three matches and most recently losing 2-1 to Liverpool. He scored 42 goals in 48 appearances in all competitions last season and won the Uefa Player of the Year award, the Golden Shoe, and both of England's domestic player of the year awards.

United will definitely be without Michael Carrick, who will be out for four to six weeks after breaking a bone in his foot, and Paul Scholes, who is suspended. Dimitar Berbatov was also considered a doubt, but trained alongside Ronaldo this morning.