Frank Lampard warned Chelsea to stay humble after they climbed to the top of the Premier League for the first time in more than two years with a convincing 2-0 win at Newcastle on Saturday.
Lampard's side moved above Leicester on goal difference thanks to Federico Fernandez's first half own goal and Tammy Abraham's strike after the interval.
Chelsea are unbeaten in nine games in all competitions and haven't lost in their last six league matches.
With five clean sheets in their last six matches in all competitions, Chelsea's third successive league victory was the perfect way to start a hectic period leading up to Christmas.
Maurizio Sarri was in charge the last time Chelsea were in pole position in the Premier League in September 2018.
But Lampard's squad are more formidable than his predecessor's fragile team and a serious title challenge looks increasingly possible.
"It's not an easy game. We played well in patches and the result is key in these games," Lampard said.
"The Premier League is tough, relentless, and we dealt with the challenge of the game very well.
"I won't get excited about being top of the table for five minutes. It's important to be humble and know it's a long race."
Chelsea could surrender top spot before the end of the day, with both Aston Villa and Tottenham able to go above them depending on their results.
"We can't have it all our own way, but we put the game away with a professional performance," Lampard said.
"First 20 minutes we were great, we had control and all the possession. I always felt that the real danger from us would be on the counter.
"You saw that with Timo Werner on the break and then setting up Tammy's goal."
Lampard had complained about having to play in the Saturday early kick off when several of his players had only returned from international duty on Thursday.
Thiago Silva was not even available to feature on the bench after the 36-year-old played for Brazil in a World Cup qualifier against Uruguay on Tuesday.
Chelsea's weary stars shrugged off their fatigue to make a strong start as Timo Werner raced onto a through ball for a low strike that Karl Darlow pushed away for a corner.
Darlow was at full stretch again when Abraham met Hakim Ziyech's cross with a powerful header that the Newcastle keeper tipped over.
The Blues' pressure was rewarded in the 10th minute when a short corner caught Newcastle flat-footed.
Mason Mount whipped in a low cross and Fernandez turned it into his own net under pressure from Chilwell at the far post.
The fifth Premier League own goal of the hapless Fernandez's career didn't sate Chelsea's appetite.
With Lampard's men monopolising possession, Werner should have doubled their lead from Mount's pass, but the German forward scuffed his shot wide from 10 yards.
Callum Wilson, who had scored six of Newcastle's 10 league goals this season, was missing with a hamstring injury and the Magpies were toothless in attack without their top scorer.
Chelsea had a golden opportunity to kill them off when Werner robbed the dawdling Fabian Schar and raced into the Newcastle area, but instead of shooting he played an awful pass that was easily cleared.
Blues defender Kurt Zouma headed just wide moments later before Chelsea had a momentary wobble.
Isaac Hayden blazed over from close-range as Newcastle finally had a sight of goal and Joelinton curled over from the edge of the area moment later.
But Chelsea put the result beyond doubt in the 65th minute when Werner accelerated away from the Newcastle defence and slipped a pass to Abraham, who guided his shot past Darlow and in off the post.
Abraham has now scored in three consecutive appearances in all competitions for the first time since September 2019.
Newcastle's Sean Longstaff hit the bar from long-range, but Chelsea's lead was never in jeopardy.
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