Sir Alex Ferguson is set to throw Cristiano Ronaldo into battle against Chelsea on Sunday after the winger was welcomed back into the Manchester United fold with open arms.

Fears that the United fans would turn on the Portugal winger over his attempts to engineer a close season move to Real Madrid proved unfounded and his appearance for the final half hour of Wednesday's goalless Champions League draw with Villarreal provided plenty of evidence that his appetite for tormenting defenders is as healthy as ever.

United should have had the match wrapped up by the time Ronaldo emerged from the bench to the biggest cheer of the night.

But there was no doubting that their cutting edge became sharper once he entered the fray, his lively display all the more remarkable for the fact that he had not even completed a reserves match since his post-Euro 2008 ankle operation.

Ferguson insisted it remained a "big ask" to expect Ronaldo to start against Chelsea but, on the evidence of Wednesday's cameo, it would be an even bigger ask to expect the manager to leave him out.

Shortly after his entry, Ronaldo instigated United's best move of the night, opening up Villarreal on the left to give Wayne Rooney the chance to tee up Carlos Tevez, whose shot was cleared off the line.

The 23-year-old also headed a good chance narrowly wide and then whipped in a cross that Jonny Evans headed against the post.

"It was his first game back so it is a big ask to think about Sunday at the moment," Ferguson said. "But he showed what he can do and he has done very well the boy."

The Scot was unsurprised by the positive reaction Ronaldo got from the fans.

"We expected that," he said. "He knows it is a great support and they have always been behind him. He deserved that, he has given us great moments and fantastic goals, the supporters don't forget that."

Villarreal boss Manuel Pellegrini admitted Ronaldo had caused his side serious problems.

"He is a great player and he was coming on fresh when there were a few tired legs out there," Pellegrini said.

Overall, Ferguson decleared himself satisfied with how his side had performed, despite a string of missed chances.

"It was difficult for some of players who have not had much football so far this season but they got through it well.

"I've no complaints. On another day we might have scored four or five."

Pellegrini admitted his side had been dominated for long periods. "The second half was much better from our point of view and we were very close to scoring but we cannot be too unhappy with the result."

A positive start by Villarreal soon gave way to sustained domination by the home side and Rio Ferdinand should have put United ahead after goalkeeper Diego Lopez's flap at an Owen Hargreaves corner, instead volleying wide from inside the six-yard box.

United were also denied two good penalty shouts for trips on Park Ji-Sung that were sandwiched around a good chance for the Korean, who was denied by Edmilson's block when he should at least have forced a save from Lopez.

A full hour had elapsed before Villarreal finally produced a response to their hosts dominance and United were fortunate to escape unpunished when Guille Franco's flick from an Angel Lopez cross came back off the inside of the post.

AFP