Manchester United had scored ten times in their last two games but they failed against bottom club Blackburn who at one stage held a two goal lead.
United clawed their way back into the game only for keeper David de Gea to hand the points to Rovers with an error ten minutes from time and hand the initiative at the top of the league to rivals Manchester City.
Steve Kean’s team had taken a point from Liverpool over the Christmas period but this result was totally unexpected and will boost the Scots claim to keep the manager’s job at Ewood Park.
For his fellow countryman Alex Ferguson it was a miserable 70th birthday as history was on his side – United had won their last seven games against Rovers in all competitions, were unbeaten in nine league games whilst their opponents had lost 11 of their 18 Premiership games so far.
Rovers opened the scoring with their first attack of the half as Dimitar Berbatov pulled back Christopher Samba and Yakubu clinically sent De Gea the wrong way from the spot kick.
Any hairdryer treatment from Ferguson at the break had little effect as Rovers quickly doubled their lead as Yakubu again found the back of the net.
But within 30 seconds Berbatov redeemed himself by pulling a goal back with a header from close range.
A typical United comeback seemed complete when the Bulgarian added his second from Antonio Valencia’s cross.
Yet this young Rovers side refused to buckle and from Morten Gamst Pedersen’s corner De Gea flapped allowing Grant Hanley to head a shock winner.
Referee: Mike Dean
Venue: Old Trafford
Man Utd scorers: Berbatov 52, 62
Blackburn scorers: Yakubu (pen) 16, 51, Hanley 80
TRIBAL ASKS: Is this the game when Steve Kean finally wins over the Blackburn fans?
Yellow cards: Nani (MU), Carrick (MU), Lowe (BLA), Petrovic (BLA)