England striker Darren Bent fired title-chasing Arsenal to a first defeat in 14 games as Sunderland battled their way to a 1-0 victory.
Bent struck 19 minutes from time to seal a tight contest after the Gunners had failed to make the most of the possession they enjoyed at the Stadium of Light.
It might have been different had keeper Marton Fulop not denied Tomas Rosicky with a vital fifth minute save or had referee Alan Wiley pointed to the penalty spot after substitute Carlos Vela went down in the box in injury time.
But the Black Cats battled all the way to the whistle to condemn the visitors to defeat for the first time since September 12.
At the start of the season, Sunderland had not beaten one of the traditional big four clubs since their return to the Barclays Premier League, but their victory today in front of a crowd of 44,918 was their first since they defeated Liverpool on Wearside on October 17.
The Gunners arrived on Wearside without star striker Robin van Persie, the subject of much discussion this week after opting for treatment on his injured ankle which included the use of horse placenta.
His absence, coupled with that of Nicklas Bendtner, left manager Arsene Wenger with few options in attack, although his team-sheet still made for impressive reading.
The Frenchman opted to field Rosicky and Samir Nasri in support of lone frontman Eduardo, and that meant he still had Andrey Arshavin in reserve on the bench.
But opposite number Steve Bruce had problems in central defence with Michael Turner suspended, and Paulo da Silva and John Mensah, back after six games out with a calf problem, found themselves fully extended at times during a tight first half.
Rosicky and Nasri repeatedly linked with Eduardo and skipper Cesc Fabregas, while Aaron Ramsey and Alexandre Song kept Lorik Cana and Jordan Henderson occupied in the middle of the field.
The Gunners might have been in front as early as the fifth minute when Fabregas expertly turned Bacary Sagna's deep cross into the path of Rosicky, who forced a good save from Fulop with a well-struck volley.
Fabregas whistled a 13th minute drive just over the bar, but Fulop was a relieved man after Song and Eduardo had combined to carve their way into the penalty area with 32 minutes gone.
The pair exchanged passes on the edge of the box and Song continued his run, only to just fail to get a touch to Eduardo's shot as it ran agonisingly wide of the post.
In the meantime, Sunderland had created two chances of their own, both of them falling to Steed Malbranque from left wing crosses.
The first saw him fire just over from full-back George McCartney's ball in, but he skied the second, with Andy Reid this time the provider, high over the bar.
Arsenal resumed in much the same vein as they took the game to Sunderland, although they were still unable to pierce the Black Cats' defence.
But Sunderland produced a flurry of their own, full-back Armand Traore just managing to cut out Henderson's 52nd minute through-ball to Bent and keeper Manuel Almunia coming from his line to claim possession with Reid putting William Gallas under intense pressure seconds later.
Almunia's goal came under threat once again five minutes later when Reid drilled a long-range free kick just wide, and the Irishman then skied a snapshot high over the bar.
Wenger's response was to replace Ramsey with Arshavin, and Bruce quickly followed suit when he withdrew Malbranque and sent on Fraizer Campbell.
But it was Sunderland's newcomer who made a swift impact with 71 minutes gone, although he did not know a lot about it.
Bent's header from a Reid corner cannoned back off his legs at the far post and fell perfectly for his strike partner to smash it home before Almunia could get there.
Wenger immediately sent on Theo Walcott and Vela for Rosicky and Eduardo, but it was Arshavin who very nearly came to their rescue with three minutes remaining.
The midfielder got to Song's cross at the far post, but he could only direct his shot into the side-netting.
But the Gunners could not believe they were not awarded an injury time penalty for Campbell's challenge on Vela with referee Alan Wiley waving their appeals away.
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