Rafael Benítez has warned there is better to come from his Chelsea side after an 8-0 defeat of Aston Villa, the heaviest in their visitors' 138-year history, propelled the European champions back to the fringes of the title race.

Seven different players found the net against Villa, with Frank Lampard, right, becoming Chelsea's highest top-flight scorer when he got the fourth just before the hour.

The victory was completed with a flurry in the latter stages as Benítez's substitutes ran riot. The victory trimmed the gap to the leaders, Manchester United, to 11 points with a game in hand, even if the perfectionist in the interim first-team manager was not entirely satisfied.

"I have my notes here and I can guarantee we can still improve little things," he said. "But the main thing is the team is still progressing and improving. We are trying to adjust the little things still in every training session – the players have been really focused from day one, wanting to learn and improve – and to see them taking effect is very positive.

"It is good news that so many are scoring, and we had other chances today, but the team is still improving. I'm sure [the title race] will be closer but still we can improve some things and I say that after winning by eight."

Lampard, who is out of contract in the summer and expecting to end a 12-year association with the club, made his 500th Premier League start here and celebrated with a fine goal. It was his 190th for the club and 130th in the top division, eclipsing Bobby Tambling's record.

"It means a lot," he said. "I've been very fortunate to play for a great club and for the managers and team-mates I've had and I'm very proud of that. Bobby Tambling is an absolute legend and a lovely bloke, so I'm proud of the goals' record as well. We're enjoying playing again now and I think we need to keep that attitude to get out of the sticky patch we were in."

This was a fifth win in six games, with 22 goals scored in four domestic fixtures, and an inexperienced Villa line-up were swept aside with ease. The visitors' manager, Paul Lambert, will need to muster a response from his crestfallen squad before the visit of Tottenham Hotspur to the west Midlands on Boxing Day. "I'm not going to sit here and make excuses … we were well beaten, second best all over the pitch," he said. "We'll have to pick ourselves up and go again on Wednesday, hurt as we are.

"I can't allow one defeat to mask over what's happened of late but we were well below our standard of late and not at the races in certain aspects of the game. But it's a really young side. Sometimes getting beat tells you a lot about people."

Chelsea expect Daniel Sturridge's move to Liverpool to go through on 1 January after the England striker underwent a medical on Merseyside on Sunday.

The 23-year-old forward, who had 18 months to run on his deal at Stamford Bridge, has fallen out of favour this season and been reduced to a bit-part role, and the London club will now prioritise the signing of a striker in next month's transfer window.