Manchester City moved eight points clear at the top of the Premier League following their 1-0 win away to Brentford even as Chelsea were held 1-1 by Brighton.
The win for Pep Guardiola's side, coupled with Brighton's 1-1 draw away to Chelsea and Liverpool's surprise defeat away to Leicester on Tuesday, gives them a comfortable eight-point cushion going into the New Year.
Phil Foden's 16th-minute goal on his return to the team after apparently being dropped for a disciplinary issue was all that separated the two sides at Brentford's Community Stadium.
Foden scored from close range after the VAR ruled he was onside as he finished Kevin de Bruyne's cross from close range, although the VAR ruled out a second goal for Aymeric Laporte for a marginal offside three minutes from time, reports Xinhua.
Chelsea looked to be on the way to a home win against Brighton when Romelu Lukaku confirmed his return to form with a 26th-minute goal, but that goal brought an impressive reaction from the Seagulls.
Chelsea looked to have weathered the storm when N'Golo Kante came off the bench midway through the second half, but Danny Welbeck's late header from Marc Cucurella's cross in the first minute of injury time gave Brighton a deserved point while denying Chelsea two vital points in the title race.
Chelsea again lost two players to injury, this time Reece James and Andreas Christensen, and that didn't help their cause as Brighton dominated proceedings either side of the interval. However, Thomas Tuchel's side appeared to have ridden the storm with a relatively comfortable final 20 minutes following the introduction of N'Golo Kante and a change of shape to bolster their midfield.
Despite the result, Chelsea rose above Liverpool into second place having played a game more than them before the two teams meet in London on Sunday.
Manchester City could take a huge step towards the title at the weekend as they visit Arsenal, whose coach Mikel Arteta is in isolation for Covid-19, while Chelsea are at home to Liverpool, in a game between their two closest rivals.