City were stunned in the 25th minute when a bizarre mix-up presented the visitors an unlikely lead. Morten Gamst Pedersen's clearance seemed likely
Related ArticlesPremier League tableTelegraph player raterManchester City v Blackburn Rovers: match previewManchester City v Blackburn: livePremier League fixturesSport on televisionto achieve little more than momentarily ease the pressure on the Blackburn defence, with both Kolo Toure and Hart converging to deal with the ball.
Yet Kolo Toure suddenly hesitated and Hart was slow to react, leaving Nikola Kalinic to roll the ball home from the edge of the City penalty area.
It was just the encouragement an industrious and well-organised Blackburn side needed to frustrate their hosts.
Indeed, there was almost further high embarrassment for Kolo Toure and his goalkeeper at the start of the second half, when the defender's back pass fell short and Kalinic was inches from popping the ball beyond Hart.
City were without Emmanuel Adebayor and Mario Balotelli but with their three English attackers, Adam Johnson, James Milner and Shaun Wright-Phillips, scurrying behind spearhead Carlos Tevez, manager Robert Mancini would have expected a greater threat on Paul Robinson's goal.
City enjoyed much possession but getting around a Blackburn back line obdurately marshalled by Christopher Samba and Ryan Nelsen was a different natter, though Robinson had to be alert with first-half saves from Johnson and Wright-Phillips.
Mancini was already contemplating the introduction of Brazilian striker Jo when City suddenly and dramatically shifted gears in the 54th minute. Tevez played in Johnson, who forced a fine save from Robinson but 60 seconds later City were level.
Vieira strode forward from midfield, found Tevez to his left and dashed forward to apply a firm finish to the Argentinian's cross.
Tevez clipped a post and Gareth Barry, who replaced Vieira in the 66th minute, had a piledriver deflected narrowly wide as City took a firm grip on proceedings.
Jo failed to convert when clean through as City dominated the closing stages. Jo and Tevez were denied by last-ditch blocks in added time as Blackburn held on.