Sir Alex Ferguson saw Manchester United maintain its impressive unbeaten start to the season and claimed his club has the depth and experience to hold on to their position at the top of the Premier League.

A Dimitar Berbatov hat-trick, with additional goals from Ryan Giggs and Nani, eased United to an emphatic 5-0 victory over Birmingham and allowed Ferguson to take key players such as Patrice Evra and Ryan Giggs out of the fray to rest for matches ahead.

United's next match is a re-arranged fixture at Blackpool on Tuesday - a game for which Rio Ferdinand (groin) and Michael Carrick, who injured his ankle in the first half against Birmingham are both doubtful, although the United manager believes his in-form team can cope.

"It helps our goal difference, no doubt about that," said Ferguson of a victory which extends United's unbeaten run to 22 league games this season, 27 dating back to last term.

"We have some tough games ahead of course. Hopefully the players can grasp the nettle. They have good experience, we've got the squad and hopefully we can manage all the games ahead.

"I was pleased with a good team performance. What helps is you score the early goal, getting a goal after a minute, they have to open up. It's a different perspective you have to face and we capitalised on that.

"It was a good scoreline at halftime and I was able to take Patrice Evra off, gave him a break by bringing on Fabio, and take Ryan Giggs off which was important because we have a big game on Tuesday."

Giggs turned in an eye-catching display, which featured a goal, on the weekend that the 37-year-old has declared that he wishes to spend at least one more season playing for the only club of his illustrious career.

"Ryan Giggs can easily play another year," said Ferguson. "He's as fresh as a daisy, we look after him the right way and he manages himself the right way. Being able to take him off was a bonus."

However, Berbatov - who has now scored 18 goals this season, 17 in the league, including three hat-tricks - was the real star of United's performance.

His pairing with Wayne Rooney looks particularly explosive at present although the England forward continued his modest goal production.

Having missed at least one glaring chance, Rooney has now scored just two league goals this season, one of them from the penalty spot.