Chelsea seized control of the Premier League title race last night as Nicolas Anelka's goal clinched a 1-0 win over Bolton to leave the Blues four points clear at the top of the table.

Carlo Ancelotti's side were well below their best as they laboured to break down stubborn Bolton at Stamford Bridge, but Anelka's header late in the first half was enough to ensure the Blues extended their lead over second- placed Manchester United.

After United's draw at Blackburn on Sunday, it was essential for Chelsea to press home their advantage and, with just four matches to play, the west London club are now firmly in position to win the league for the first time since 2006.

Alex Ferguson's claim that Bolton would be an "easy" game for Chelsea had drawn an amused response from Ancelotti, who was quick to dismiss the United manager's mind games, and Wanderers made the leaders sweat right until the final whistle.

Yuri Zhirkov was left with a bloodied head wrapped in bandages following an aerial collision with Kevin Davies. The Russian was twice forced to leave the field to patch up his bleeding wound before half-time.

But the Russian returned to play his part as Chelsea took the lead just before the break.

He rolled a pass wide to Drogba on the left wing and the Ivory Coast striker whipped over a perfect cross that Anelka met with a close-range header which gave the keeper no chance.

It was Anelka's first goal in 14 matches since he last netted at Burnley in January and provided the perfect response to this week's claim from Bolton striker Davies that his former Wanderers team-mate wasn't happy playing alongside Drogba.