A dreadful Steven Gerrard blunder set Chelsea on their way to a 2-0 victory at Liverpool on Sunday and moved them to within one win of the Premier League title. The England midfielder needlessly delivered a back-pass that was intercepted by Chelsea striker Didier Drogba, who rounded keeper Pepe Reina and slotted into an empty net after 33 minutes. Chelsea, bidding to win their first league title since 2006, killed off the game nine minutes after the restart. In-form midfielder Frank Lampard converted Nicola Anelka's low cross from close range for his 21st league goal of the season. Leaders Chelsea have 83 points, four ahead of second-placed Manchester United who can cut the deficit to one point if they beat Sunderland later in the day. A victory for Chelsea at home to Wigan next week in their last league game will give them the prestigious title in their first season under Italian coach Carlo Ancelotti. Gerrard blunder