Chelsea labored to a 1-0 victory over Middlesbrough to keep pressure on Premiership leaders Manchester United, thanks to an early header by Ricardo Carvalho. The Portuguese center-half fired in Wayne Bridge's free kick to beat Mark Schwarzer after six minutes. Egyptian midfielder Mohamed Shawky was introduced in injury time, replacing Lee Cattermole, but he barely got a touch of the ball. Chelsea reached 71 points to restore their position as runners-up to United, with six games to go. Boro, who missed injured forward Ahmed Hossam 'Mido', remained 12th with 34 points.