Sir Alex Ferguson expects Cristiano Ronaldo to be crowned world and European player of the year in December - but revealed he could leave the winger out of tomorrow night's Champions League match with Celtic.

After scoring 42 goals last season, Ronaldo has already found form this term, rattling home his fourth of the season in Manchester United's comfortable weekend win over West Bromwich Albion.

Ferguson says he cannot see any reason why both Ronaldo shouldn't win both awards. "Cristiano will win both player of the year awards, I am sure of it," he said. "If he doesn't, I want to sign the guy who does."

However, Ferguson feels Ronaldo has not quite recovered from the ankle operation he had in the summer and says he is tempted to rest the player against the Scottish champions. "Cristiano is still finding it hard to recover from a Saturday game to a Wednesday," he said. "I need to look at this game and the fact it is on a Tuesday and assess whether to bring in Nani."

Ronaldo remains keen to play in every match, and Ferguson says he saw how the 23-year-old responded to Gary Neville's query about his fitness at Old Trafford on Saturday and knows he faces a delicate decision.

"I thought Cristiano was starting to show signs of tiring so I asked Gary to see how he was," Ferguson said. "Ronaldo said he was feeling it a bit and maybe it was time to come off. Five minutes later he told Gary he felt good. Maybe it was the thought he might be coming off.

"But you will find that. The type of human being he is and the type of athlete he is, he always finds something extra. He was magnificent on the Saturday against Sweden but when Portugal played Albania last Wednesday he was a bit flat. It is simply because of the recovery thing."

While Ferguson's dilemma will probably not be resolved until an hour before kick-off, he does not intend to spend any time worrying about Ronaldo's subdued reaction to the 95th goal of his United career. The player's response has been viewed by some as an indicator the player wished his dream move to Real Madrid had gone through this summer. Ferguson, who persuaded him to stay, is not getting involved. "I read that stuff," he said. "I am not even going to answer it."