After 73 minutes of tedious stalemate, the Ivory Coast striker attempted to control a free kick from defender Paulo Ferreira, only for the ball to bounce off his knee and creep inside Jens Lehmann’s near post.
Arsenal, last year’s runners-up, coped comfortably against a subdued Chelsea strike force and looked the slicker side for long periods, despite the second-half introduction of Chelsea’s new 38 million euro ($46.47 million) signing Michael Essien.
Thierry Henry blazed one shot wide early in the second half for the Gunners but, once they fell behind, they struggled to open up a Chelsea defence well-marshalled by John Terry.
Victory put Chelsea on six points from two matches, level with Tottenham Hotspur, Charlton Athletic and Manchester United.
Meanwhile, a second-half goal by Marcus Bent earned Everton a 1-0 victory against Bolton Wanderers and their first points of the Premier League season.
Beaten 2-0 by Manchester United in their season-opener last weekend, Everton sparked into life after a dull first half.
Striker Bent broke the deadlock at the Reebok Stadium in the 52nd minute with a left-footed shot following a pass from Tim Cahill.
Bolton piled on the pressure in the closing stages and almost equalised in the 87th minute but El-Hadji Diouf’s effort bounced off the crossbar.
The result lifted the Merseyside club to 11th in the standings after two games while Bolton dropped from seventh to 12th.
Japanese midfielder Hidetoshi Nakata, who joined Bolton on loan from Fiorentina earlier this week, did not play in the match.
Results:
Played on Sunday:
Bolton Wanderers 0 Everton 1
Chelsea 1 Arsenal 0
Played on Saturday:
Birmingham City 1 Manchester City 2
Blackburn Rovers 2 Fulham 1
Charlton Athletic 1 Wigan Athletic 0
Liverpool 1 Sunderland 0
Manchester United 1 Aston Villa 0
Newcastle United 0 West Ham United 0
Tottenham Hotspur 2 Middlesbrough 0
West Bromwich Albion 2 Portsmouth 1
—Reuters