Late comeback keeps Blues title hopes alive.
Talk from the home camp before the match centered on building upon Wednesday's win over Bolton and with the top three all winning, anything less would have seen the Blues arguably lose too much ground to still be considered title challengers.
Manager Carlo Ancelotti was forced to hand 19-year-old defender Jeffrey Bruma his first ever Premier League start for the Blues thanks to Branislav Ivanovic's, Alex's long term injury suspension and Paulo Ferreira doing such an awful impression of a center-back against Sunderland.
And the youngster had his side's first chance at the other end, heading Frank Lampard's corner goalwards, only for Carlos Cuellar to clear six minutes in. Three minutes previously Gabby Agbonlahor had drilled a shot just wide of Petr Cech's right hand post as the Villans looked to take the game to their hosts.
And it was the away side again pressing for the opener 10 minutes later when Ashley Young's in-swinging cross fooled everyone and had Cech at full stretch to tip over for a corner, before Stuart Downing stung the Czech shot-stopper's palms with a rasping drive from 25-yards.
As the 20 minute mark approached it was Villa in the ascendancy and while Chelsea's passes reeked of desperation and hopefulness, Gerard Houllier's side were calm and composed in possession with the midfield five linking up nicely as the claret shirts swept forward.
But the pendulum swung the other way thanks to a contentious decision that resulted in a spot kick for Chelsea. Lampard's looped ball was nodded away by James Collins with Florent Malouda crumpling to the floor under his challenge. Referee Lee Mason pointed straight to the spot, to much protestation from the away side, for which Brad Freidel saw himself enter the book.
Lampard stepped up to smartly dispatch the spot kick - only his second goal of the season after a long absence with injury.
And Villa's frustrations boiled over. Young was penalized for a late challenge on John Terry, with the home faithful baying for harsher penalty. It became full blown pantomime when Cole went down theatrically under another Young challenge, this time Mason waved play on.
With half an hour gone Villa defender Ciaran Clark headed a Young corner over from eight yards out. It was a good chance and his reaction indicated he knew it. Richard Dunne had an even better chance eight minutes later after a Downing chip found him at the back post but he sliced his shot over the bar.
But just five minutes before the break The Villans had a penalty of their own and Michael Essien's swung through Reo-Coker sending the midfielder sprawling and Young had a chance to silence the home crowd as he confidently smashed the ball high past Cech. Of course, it wasn't met with silence but even louder boos than before.
As the half-time whistle went Villa had amassed an impressive six yellow cards in what can only be described as a feisty first period; Agbonlahor and Clark adding their names to the list late on with reckless challenges meaning Villa will receive an automatic £25,000 fine. An expensive 45 minutes' work.
The second half was barely 90 seconds old when Villa took the lead. Downing wriggled his way to the byline and held the ball up at the far post when Emile Heskey rose highest to nod past Cech. It was not the start to the second period Chelsea were planning and to say the home team were stunned is an understatement.
It was an unlikely source trying to bring the home side back into it, but the emergence of Ramires is one of the few positives at Stamford Bridge at the moment. The impressive Brazilian capitalized on a loose ball on the right of the six-yard box but drilled his shot wide of the far post.
As the hour mark came and went frustration mounted from the 40,000 home fans but they were on their feet as Lampard met Drogba's nod down to volley at goal, with only a fine Friedel save stopping him bringing the Blues level.
And the American was at it again, getting down fast to deny Malouda who had been played in by an excellent Lampard pass. But the opportunities lifted a clearly self-conscious Chelsea and they piled forward looking for more. Sadly for them they found a resolute Villa defense and goalkeeper in the way.
Substitute Soloman Kalou brought the best out of Dunne with a silky run that the Villa defender did well to block as the Blues threw everything forward in a bid to save a precious point.
And the move worked as with just seven minutes left a ball from the left found the Ivorian who's shot was blocked by Friedel, but the ball fell to Drogba who made no mistake in the six-yard box. Cue euphoria mixed with relief from the home fans.
The final few minutes saw an onslaught on the Villa goal with every ball headed away and blocked until Drogba's header was palmed away by Friedel to captain Terry who calmly side-footed home to send the home faithful into raptures.
But the Villans went right down the other end to pull themselves level as Clark met Albrighton's beautifully curled cross to nod past a static Cech.
Chelsea piled forward in the final seconds but couldn't an even later winner and the final whistle means they are five points off top spot after an entertaining, but ultimately frustrating, afternoon.
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