Alex Ferguson is convinced the goals will soon start to flow again for Manchester United after his side were held to a 0-0 stalemate by Villarreal at the start of their Champions League defence, extending a run that has now seen them win only once and score just four times in their opening five matches.

With Dimitar Berbatov missing out after picking up a knee injury at Liverpool at the weekend, United are hardly in the best of form heading into Sunday's showdown with Chelsea at Stamford Bridge.

However, Ferguson is confident it will not be long before United are hitting the net on a regular basis again.

"We will improve from now," he said. "We are a bit short but the games will bring us on.

"It was the same last season. It wasn't until we got a victory over Sunderland that we really got on the road.

"We have a little bit to go yet. But once the sharpness of play comes I am sure the goals will come as well."

Ferguson was happy with United's overall performance, in which Jonny Evans hit a post late on and Carlos Tevez had a second-half effort cleared off the line.

However, the major plus was Cristiano Ronaldo's earlier-than-expected return from ankle surgery.

After the will-he, won't-he transfer saga involving Real Madrid, many pundits wondered what kind of reception Ronaldo would get from the Old Trafford faithful.

In the end, just as Ferguson predicted, there was nothing but support.

"We expected Cristiano to get a great reception," said the United boss. "He knows the supporters have always been behind him. He has given us great moments and scored some fantastic goals.

"Maybe he was a bit apprehensive but he shows great loyalty and commitment every time he puts that jersey on."

However, Ferguson is not willing to write Ronaldo into his plans for Stamford Bridge just yet given the Portugal star has just spent over two months on the sidelines.

"That was his first game back, so it is a big ask to think about Sunday," said Ferguson. "To come back like that, without a practice match or anything, the boy has done very well."

Ferguson is equally reluctant to confirm Berbatov's participation, although the €37million striker will be given every chance.

"Dimitar has a chance for Sunday but it is too early to say for certain," he said.