London - Frank Lampard scored four as Chelsea stepped up their Premiership title challenge with a 7-1 thrashing of Aston Villa at Stamford Bridge on Saturday to inflict the visitors worst top flight defeat in 23 years.
England midfielder Lampard put his side ahead in the 15th minute and restored the lead from the penalty spot after John Carew had equalised for Villa in the 29th minute.
After the second half though, the Blues took total control with Florent Malouda netting twice and Lampard adding two more as he took his Chelsea career tally past 150 goals.
Chelsea, who thrashed basement club Portsmouth 5-0 in midweek, went two points in front of reigning champions Manchester United, who were playing Bolton in Saturday's late kick-off.
The result will inevitably have a major bearing when Chelsea and Villa meet again in the FA Cup semi-final on April 10.
But more importantly, this win maintained the pressure on United ahead of Chelsea's visit to Old Trafford next weekend.
Chelsea's rout of Portsmouth had restored confidence at Stamford Bridge following the Champions League defeat by Inter Milan and subsequent draw with Blackburn Rovers.
Blues boss Carlo Ancelotti left leading scorer Didier Drogba on the bench with the Italian handing experienced striker Nicolas Anelka the responsibility of spearheading the attack.
Anelka has looked out of sorts in recent weeks and had failed to score in his previous 10 appearances coming into this game.
But the France international started impressively and played a part in the goal, laying off for Malouda who delivered a low cross that was turned in by Lampard at the far post.
It was Lampard's 14th goal in 30 league appearances and with Villa struggling to get forward, appeared to lay the foundations for Chelsea to establish a firm grip on the game.
The Blues dominated possession but were frustrated in their efforts to carve out a second meaningful opening, with Ancelotti becoming increasingly agitated as a series of decisions went against his side.
And the Italian had even greater cause for frustration when he saw his side undone in the 29th minute by Villa winger Ashley Young.
Young was picked out by an excellent pass from Steve Sidwell and given too much space by the back-tracking home defence as he cut in from the left flank before producing a carbon-copy of Malouda's cross towards John Carew.
Carew couldn't fail to convert and unexpectedly Villa were level.
Chelsea had only themselves to blame, but they forced their way back into the lead two minutes before the break when Yuri Zhirkov burst into the Villa box and was brought down by James Collins.
Lampard converted comfortably from the spot, no doubt sparing his team-mates from a half-time dressing down from Ancelotti.
The goal appeared to have lifted the home side and Chelsea played with greater freedom during a second half in which they completely out-classed the visitors.
Malouda established a two-goal advantage in the 57th minute from Zhirkov's left wing cross and from that point there was never any question of Villa getting back into the game.
Lampard completed his hat-trick from the penalty spot after Zhirkov again surged forward and was brought down by Richard Dunne.
Malouda made it five with a right foot finish in the 68th minute.
Kalou made it six seven minutes from time and Lampard drilled home his fourth in added time.