Chelsea narrowed Manchester United's lead in the Premier League to four points on Tuesday with a 1-0 victory at Portsmouth while Liverpool also kept their slender title hopes alive with a 2-0 defeat of Sunderland.
United have two games in hand on both, starting with their trip to struggling Newcastle United on Wednesday.
Fifth-placed Arsenal ended their recent goal famine when Nicklas Bendtner scored twice in a 3-1 victory at bottom club West Bromwich Albion which put them just three points behind Aston Villa in the race for a top-four spot.
Chelsea were unimpressive in torrential rain at Fratton Park and the home side had two glorious opportunities to go ahead before Didier Drogba's fine finish 11 minutes from time settled the points.
It was Chelsea's fourth consecutive victory by the odd goal since Guus Hiddink replaced Luiz Felipe Scolari as manager.
Chelsea have 58 points from 28 games but are above long-time leaders Liverpool on goal difference.
Liverpool went ahead seven minutes after the break when Steven Gerrard headed the ball across goal for David Ngog to tap in his first Premier League goal.
The home side doubled their lead when keeper Marton Fulop made a meal of saving an overhead kick from Ngog and Yossi Benayoun, who scored the winner in the Champions League victory at Real Madrid last week, tucked in the rebound.
