If Alex Ferguson is still making New Year's resolutions at the age of 70 his hopes for 2012 should be for Manchester United to shake off the lethargy that has handed the Premier League initiative to Manchester City and for an end to their injury blight.

Ferguson's birthday on Saturday was soured by a shock 3-2 home defeat by then bottom club Blackburn Rovers which meant the champions ended 2011 second in the table on goal difference and gave City the chance to go three points clear when they travel to Sunderland on Sunday.

Ferguson branded the loss a "disaster", while pointing to injuries that have prevented him fielding a consistent line-up and forced him into playing men out of position such as midfielder Michael Carrick in central defence.

"We're having problems with all the four central defenders out at the moment so we're missing the craft and experience of Michael Carrick in the middle of the pitch," Ferguson said.

"We played Park Ji-sung and Rafael in centre midfield (against Blackburn), but they aren't centre midfielders."

Captain Nemanja Vidic is out for the season, while fellow central defenders Chris Smalling, Rio Ferdinand and Jonny Evans are also sidelined. Midfielder Darren Fletcher is taking a break due to a bowel condition and Tom Cleverley and Ashley Young are injured.

So numerous are the absences that Ferguson gave midfielder Anderson a sooner-than-expected return to action with the Brazilian coming on at halftime on Saturday when he had initially been ruled out until February with a knee injury.

"We have a lot of injuries at the moment and I had to take a gamble on Anderson's fitness," he told the club's website.

"He's been training very well for 10 days but it was his first game back and it wasn't easy for him. But he didn't let us down. He did his best."

With talk of a "gamble" on Anderson, there were therefore some raised eyebrows when top scorer Wayne Rooney did not even make the bench against Blackburn because of what Ferguson said were "little strains here and there".

Unsourced local media stories reported Rooney had been left out as a disciplinary measure but Ferguson merely said he should be should be fit for Wednesday's trip to Newcastle United.

By the time they head to the northeast, United could find themselves six points adrift as City play twice before that.

They will want to rediscover the verve that propelled them to five successive league victories before the Blackburn defeat, including back-to-back 5-0 wins, after a laboured display on Saturday.

Ferguson blamed a "boggy" Old Trafford pitch for the lack of fluency, while defender Phil Jones could offer no explanation when asked why they had displayed so much lethargy.

"The injuries don't help but it's no excuse. We weren't good enough, nowhere near good enough. We've just got to kick on from here and get back to winning ways," Jones told MUTV.

"We were too slow, too laboured and not quick enough. We're just generally disappointed."

Ferguson, who earlier on Saturday said he expected to stay at United for another three years, was determined to put the setback behind him as they chase a 20th English league title.

"We know we can improve on today's performance," he said. "We won't get many like that. I'm confident we'll give it (the title) a real go."