Yossi Benayoun came off the bench to head a late winner as below-par Arsenal triumphed at Aston Villa.
Villa had chances to open the scoring before Robin van Persie scored his 34th goal of 2011 from the penalty spot after a foul on Theo Walcott.
Marc Albrighton capitalised on a defensive error to slot in the 20,000th goal in Premier League history.
But Benayoun won it from Van Persie's corner, while Villa's Alan Hutton was sent off for two yellow cards.
The Scot was shown his second for a late tackle on Thomas Vermaelen, just moments after picking up his first caution for dissent.
That compounded a bitterly disappointing finish for Villa, who have now won only two of their last 10 matches - losing four of the past six.
Boss Alex McLeish spoke beforehand about the need to stop conceding "stupid goals" from set-pieces, but that is exactly what happened.
They let Van Persie's corner drift through the goalmouth to an unmarked Benayoun and he converted his first top-flight goal for Arsenal.
The Gunners return to winning ways after Sunday's defeat at Manchester City and have lost only one of their last 10 league matches.
Arsene Wenger's men have still not been beaten at Villa Park since December 1998, and captain Van Persie continues to shine.
The Dutchman has equalled Thierry Henry's club record for goals in a calendar year and is two behind Alan Shearer's Premier League record from 1995.
On this occasion, his strike came completely against the run of play.
With midfielder Francis Coquelin starting at right-back, regular centre-half Vermaelen at left-back and Emmanuel Frimpong deputising for the suspended Alex Song in the holding midfield role, Arsenal looked extremely vulnerable in the early stages.
That was until Arsenal's first meaningful attack. Walcott collected Mikel Arteta's throw and tricked his way past Ciaran Clark before the Villa man tugged at his shirt.
Referee Jon Moss pointed to the spot and Van Persie slammed the ball high past Brad Guzan.
Moments later, Walcott had an excellent chance to double the lead when sent clear by Van Persie, only for Guzan to race out and get a hand to his lob.
Villa were swiftly back on top, though, and Wojciech Szczesny did well to gather another cross - this time from Albrighton - with home players queuing up to tap home.
Villa were gifted a deserved route back in shortly after the break as Vermaelen sold Per Mertesacker short with a simple pass.
As Mertesacker hesitated, Albrighton poked the ball around the Germany international, then slotted past Szczesny for the landmark strike.
After levelling, lone-striker Gabriel Agbonlahor began to look increasingly isolated, while Arsenal pushed for the winner.
Van Persie was cautioned for diving despite falling under a strong challenge from Stephen Warnock, Richard Dunne blocked from substitute Tomas Rosicky and Andrey Arshavin, another replacement, saw a shot deflected just over the bar.
The pressure eventually told when Benayoun pounced from Arsenal's 15th corner before Hutton saw red.
Aston Villa manager Alex McLeish:
"We were totally [unlucky]. Arsenal had a lot of corners in second half and unfortunately we lost out on one. But it was much more a performance of the team I'm trying to coach. We were very dynamic and played as team with outstanding individual performances. It was a tremendous display.
"I'm so pleased to see the players getting up in support of Gabby, it was such a positive performance by the players. We were tired at the end.
"But going into a really tough schedule you can do without players getting sent off. Alan should know better, he had a rush of blood to head. He's a vital player to the squad and we'll now miss him. Bent was close tonight and I certainly expect him to be ready for Monday."
Arsenal manager Arsene Wenger:
"We knew we would have a difficult game. We've given a lot in the last three days physically. Villa played well. In the second half we went through a difficult period but we kept going and showed this team has quality, they never give up.
"Yossi has had to wait for his moment but he has been 100% professional and got us three very important points. He works hard and shows fantastic attitude. It was the kind of game that could have gone either way, it was very physical.
"The injury situation is not looking good - the full-backs will not be back before mid-to-late January. We have to see who can play there from game to game and be creative."