And lo, it came to pass that on the 70th birthday of the manager who originally thought he would be ready to retire a decade ago, the honour of ascending the table was stolen by the manager whose shelf life has lately been counted in days, if not hours.

Manchester United did not knock Manchester City off the top of the Premier League in time for Hogmanay after all, but one Scottish manager was left with every reason to celebrate. Blackburn climbed only two places as a result of this unlikely yet deserved first away victory of the season, and maybe only briefly, but after claiming a draw at Anfield on Boxing Day even Steve Kean's many doubters will have to concede the promised turnaround in the club's fortunes may be achievable after all.

Sir Alex Ferguson, thoroughly deflated after suggesting beforehand that he hoped to stay on as United manager for another three years, was left blaming a heavy pitch and a run of injuries. There is no doubt that United do have injuries, but so do Blackburn, who have a much smaller squad, and both sides had to play on the same pitch.

"It was a very physical game, because the wetness of the pitch made everything such hard work," the Rovers manager said. "When United pulled it back to 2-2 they got the crowd behind them but they were not able to build up their usual head of steam because we dug in so well. We have learned from recent defeats. We no longer just lash the ball up the field, we try to pass our way forward."

The birthday tributes to Ferguson were all well deserved, but the sage of Old Trafford possibly underestimated the bottom team in his attempts to return to the top. If Ferguson had been paying attention to Blackburn's creditable draw in their last game he would have known that their new strategy is to lull opponents into a false sense of security then try to nick a goal from a set piece.

They repeated the Liverpool routine here. For the first 10 minutes the game resembled a melee in a junior school playground, with all the action around one goalmouth and people queueing up to take pot shots at Mark Bunn's goal, but when Patrice Evra carelessly conceded a free-kick after showing too much of the ball to Mauro Formica after 15 minutes Dimitar Berbatov even more clumsily pulled over Chris Samba in the area and Yakubu Ayegbeni put Rovers ahead from the penalty spot.

Suddenly it did not seem such a good idea to rest Wayne Rooney, try Rafael da Silva in midfield and use Michael Carrick as a centre-half, even if the last decision was forced on Ferguson by circumstance. United were not forceful enough in midfield to chase the game with their usual vigour and neither did they have options on the bench to counter Blackburn's organised defending and willingness to get men behind the ball. Ferguson seemed reluctant to try Paul Pogba, despite repeatedly saying he is almost ready. There were shots from Nani, Phil Jones and Javier Hernández before the interval, but nothing demanding heroics from Bunn until Nani brought a diving save on the stroke of half-time.

Ferguson opted to send Anderson on for the second half, in place of the disappointingly ineffective Hernández, with Rafael and Antonio Valencia reverting to their more customary positions on the right flank and Danny Welbeck pushed up front.

United improved almost immediately, though before Berbatov put them on the scoresheet with a header from Rafael's volleyed cross, Yakubu exposed the frailty at the heart of the home defence by bursting past Carrick and Jones to put Blackburn briefly two ahead.

Berbatov cut that deficit within a minute to set up an absorbing final half-hour, but with more players back in their normal positions United were making inroads for the first time and Berbatov had a second just after an hour, sweeping a shot past Bunn after Valencia had cut back from the right-hand byline for the striker's sixth goal in three games.

Valencia enjoyed himself so much in the second half it rather mocked Ferguson's decision to start him at right-back, but he could not keep his shot down when he had a chance to put United ahead 15 minutes from time.

The script was beginning to follow a familiar plotline, but just when it appeared United would press on to score a winner Blackburn raised the stakes again. An enterprising run from Adam Henley won a corner off Jones, and from Morten Gamst Pedersen's cross David de Gea somehow allowed himself to be twice beaten in the air by Grant Hanley. The centre-half's first header went straight up in the air and, with De Gea flailing, his second was unchallenged and found the back of the net.

United could not hit back again, could not even build up the usual head of steam. Their best chance came right at the death when Jones's shot was cleared off the line, by one of his team-mates as it turned out. That was bad news for William Keane, a late United substitute, but a splendid New Year present for Steve Kean, off the bottom of the table with a famous win.

"We are desperate for wins and it was great to get one here," the Rovers manager said. "This is such a young team, because of all the injuries we have and this is the sort of result that can really make a young lad's career. The victory is massive for everyone at Blackburn, but it's no use if we don't build on it. We need more wins to climb the table and now we have got to go on and do the same professional job in our next games."