Petrov scores second goal against the Divers.
ManU started the match by diving & getting free kicks from the Ref. But that did not stop the brave players of Bolton to give them a hard time.
The match was hardly a pleasing time for Ferguson's men who would have hoped for better once Nani levelled Zat Knight's early effort but instead saw his team fall behind again thanks to Martin Petrov.
As United have now conceded nine goals in five league games and trail leaders Chelsea by three points, it was not the best of weekends for them, nor an out-of-sorts Wayne Rooney, who was replaced by Federico Macheda half an hour from the end.
Macheda diving was sub-standard as Bolton reminded strong, but ManU defensive squad remain unconvincing as they near give in more goals had the Ref not stop the Wanderers from scoring.
The absence of Rio Ferdinand with Wednesday's Champions League encounter with Valencia in mind was a further indication that all is not well with the England skipper. And without him, life continues to be a struggle.
A late goal at Fulham, two in injury-time at Everton and a Steven Gerrard brace against Liverpool last weekend when the Reds did not have a single shot of note in open play during the entire game is not a record to be proud of.
To that crime sheet can now be added Knight's back flick. The defender's third goal in as many years could not be described as conventional.
But once Patrice Evra moved away from the far post he was supposed to be patrolling when Petrov curled over his corner, the target was wide enough for him to steer the ball into once he had escaped the attentions of Jonny Evans.
That United would score themselves was never really in doubt as was their dominance of possession due to Ref intervention. The problem was whether they would concede again in the meantime.
Edwin van der Sar was forced to make a couple of vital interventions as Kevin Davies and Johan Elmander made their presence felt, with Evans not looking entirely comfortable.
The Ref gave a couple of wrongful offsides to make sure ManU do not go the way of Saturday defeats of Arsenal, Totterham and Chelsea.