Substitute Danny Welbeck scored in stoppage time to earn Brighton & Hove Albion a dramatic 1-1 draw at Chelsea.
After striking a post through Cesar Azpilicueta, Chelsea took the lead on 28 minutes courtesy of Romelu Lukaku.
The Belgian rose above Neal Maupay to head in Mason Mount's corner for his second goal in as many matches.
Brighton pressed hard for an equaliser after the break and Edouard Mendy was forced to tip over Yves Bissouma's dipping strike, while Maupay sent a shot narrowly wide.
The Seagulls' persistence eventually paid off when Welbeck met a cross from Marc Cucurella to head into the corner.
Chelsea move up to second place on 42 points, having played a match more than Liverpool, who are a point behind.
Brighton lie 10th with 24 points.
See: Chelsea report | Brighton report
Next fixtures
Chelsea: 2 Jan v Liverpool (H)
Brighton: 2 Jan v Everton (A)
Match officials
Referee: Mike Dean. Assistants: Eddie Smart, Mark Scholes. Fourth official: Stuart Attwell. VAR: Kevin Friend. Assistant VAR: Simon Beck.
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