John Terry grabbed the only goal of the game to extend
But a makeshift United side will feel aggrieved after a fine display, with Darren Fletcher in impressive form. Wayne Rooney twice went close from range, but a lack of cutting edge cost the reigning champions dear in the end.
And with Sir Alex Ferguson's side now five points behind their London rivals, United must hope Chelsea's current form falls away if they are to win a fourth successive title. They can at least be comforted by a brave performance, though, especially considering the absence of centre-half pairing Rio Ferdinand and Nemanja Vidic, as well as striker Dimitar Berbatov.
While it remained 0-0, Ferguson - mindful of his side's failure to get anything out of four of their last five away matches against a 'big four' team - was by far the more comfortable manager and it was Blues boss Carlo Ancelotti who blinked first from the sidelines, bringing on Joe Cole for the ineffective Deco.
But it was Rooney at the other end who twice came closest to breaking the deadlock, his first effort a drive inches wide from the edge of the area and the second a curler that had to be tipped round the post by Cech.
However,
To compound the visitors' deflation, United had argued that Fletcher, in conceding the crucial free-kick, had won the ball from Ashley Cole and that Drogba was in an offside position as the ball flew in - but their protests fell on deaf ears. (BBC Sport)