LONDON - Michael Essien's first-half header was enough to give 10-man Chelsea a precious win over their London rivals and extend their lead atop the Premier League to four points after the Manchester sides lost ground following their derby draw.

The Ghana midfielder met Florent Malouda's pinpoint cross into the six-yard box and sent the ball into the bottom corner in the 30th minute. Essien was then shown a red card in the final moments of injury time for a two-footed lunge on Clint Dempsey.

But the sending-off came too late to make a difference for Fulham.

"It was a good performance," Chelsea manager Carlo Ancelotti said. "We started well from the beginning with a high tempo during the game. The first half was very good and we had good control in the second half. We had a little problem at the end, but this is normal."

Salomon Kalou wasted three good chances to increase Chelsea's lead, and goalkeeper Petr Cech had to tip Dempsey's late 25m shot over the bar to ensure the win.

Didier Drogba tested Schwarzer in the 28th minute with an angled 30m free kick before Chelsea broke the deadlock when Kalou's cross was headed down and into the net by Essien.

The goal was scored while Drogba lay injured inside the penalty area and he required treatment before the game could restart.

"That's a disappointment from our point of view. We were distracted by Drogba lying prone in the box," Fulham manager Mark Hughes said. "You still have to play to the whistle, so maybe we were guilty of expecting the referee to blow up. He didn't and we paid the penalty. It's confusing the way the game is viewed in terms of when players go down: are they faking, and do you kick the ball out?'' AP