Manchester United moved eight points clear at the top of the Premier League after a hard-fought win over Blackburn.
Wayne Rooney lashed in a shot to put United ahead before a precise Roque Santa Cruz finish levelled matters.
Jonny Evans' header was controversially disallowed for the home side before Ryan Nelsen hit the post for Rovers.
Cristiano Ronaldo powered in a superb free-kick for United's winner, and Morten Gamst Pedersen was denied a penalty late on for the visitors.
The Norwegian winger looked to have been pulled back by Rafael Da Silva when he was clean through on goal and the decision not to award a spot-kick provoked a furious response from Blackburn boss Sam Allardyce.
But given Rovers are third from bottom and two points away from safety, Allardyce's side can be encouraged by their display, troubling a United side that has been sweeping aside all before them in recent weeks.
Allardyce frustrated by penalty controversy
Blackburn also have the honour of becoming the first side to score against United since 8 November, 2008 when Sir Alex Ferguson's side were beaten by Arsenal.
With United playing Inter Milan on Tuesday, Edwin van der Sar and centre back Nemanja Vidic were left on the bench with Tomasz Kuszczak and Evans left to fill the key roles, a policy that almost backfired on the Scot as Blackburn threatened to steal a point.
Not that there appeared any likelihood of that in the early stages of the game.
Blackburn were sloppy in possession and their defence was creaking as Nelsen hooked a Ronaldo cross away at the far post with Rooney waiting to tap in.
Patrice Evra put a follow-up strike just wide as United patiently passed and probed in the knowledge a goal would come.
Sure enough it did when Nani curled in a low cross, and although the outstretched leg of Nelsen got a touch to the ball, it was not enough, and Rooney pounced to score from close range.
But Rovers regrouped and were soon level as United conceded only their 11th league goal this season.
Andre Ooijer stole the ball from Nani and slid a pass through to Santa Cruz, who rode a Rio Ferdinand challenge, rounded keeper Kuszczak and slotted in.
Pedersen bemused by decision
The goal gave Blackburn an injection of confidence and their closing down became sharper as United's play fell away.
Evans thought he had restored the home side's lead with a header from a dubiously awarded corner, only for his effort to be ruled out for a Ronaldo push on Nelsen.
The New Zealand defender was soon in the thick of the action again, though this time in the United box, as his first-time shot came back off the woodwork, with El-Hadji Diouf's effort from the rebound saved by Kuszczak.
Phelan pleased to open up lead
Ronaldo punished the visitors for the miss when he angled in a free-kick from just outside the left edge of the area with a stunning strike.
The Portuguese had earlier been booked for diving and might not have been on pitch had he also been carded for kicking out at David Dunn.
Blackburn will also feel aggrieved that they did not get a penalty when Pedersen went down in the closing stages.
Blackburn boss Sam Allardyce:
(On the penalty decision) "I think he's pulled him, got his arm on his shoulder.
"It's not so, so blatant but he's through on goal and it's put him off balance and it's not given but I wasn't surprised.
"It's difficult to play here so it's difficult to ref here as well but they're prepared to do the job and get it right like we are, and when they get it wrong then they need to be held accordingly to that.
"From our point of view what we could control we missed, and that was the Ryan Nelson miss."
Manchester United assistant manager Mike Phelan:
"We've done our job, that's all we can do so now we move on to the next one.
"It's never easy playing against Sam Allardyce's teams and that was shown today.
"Games seem to be about controversy all the time. I think the referee is right on the spot and he didn't give it.
"We can only stand by what the officials do."
Man Utd: Kuszczak, Rafael Da Silva, Ferdinand, Evans (Vidic 64), Evra, Ronaldo, Carrick, Scholes (Giggs 82), Nani (Tevez 64), Rooney, Berbatov.
Subs Not Used: Foster, Welbeck, Fabio Da Silva, Fletcher.
Booked: Ronaldo, Berbatov.
Goals: Rooney 23, Ronaldo 60.
Blackburn: Robinson, Ooijer, Nelsen, Givet, Warnock, Grella (McCarthy 79), Diouf (Treacy 83), Andrews, Dunn (Kerimoglu 73), Pedersen, Roque Santa Cruz.
Subs Not Used: Brown, Khizanishvili, Mokoena, Roberts.
Booked: Andrews, Givet.
Goals: Roque Santa Cruz 32.
Ref: Howard Webb (S Yorkshire).
BBC Sport Player Rater man of the match: Manchester United's Wayne Rooney on 7.68 (on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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