Chelsea fell to a last-gasp 1-0 defeat against Newcastle at St. James' Park on Saturday, thanks to Isaac Hayden's stoppage time winner.
Frank Lampard's side were unable to build on last week's emphatic 3-0 victory over Burnley, instead recording their eighth defeat of the season.
Chelsea dominated the match, but were made to pay after failing to clear a corner and Hayden powered home a header four minutes into stoppage time.
Striker Joelinton came close to scoring the opening goal when he rattled the crossbar on 21 minutes with a thumping header from the penalty spot.
Chelsea Right-back Reece James looked to be his side's most potent creative threat in the first half, with the 20-year-old defender delivering a significant number of crosses into the Newcastle penalty area, although few led to meaningful chances.
James was substituted on 74 minutes after twice going down injured.
The visitors dominated a forgettable second half, with striker Tammy Abraham enjoying the best chance to break the deadlock when he touched the ball past goalkeeper Martin Dubravka before slicing his close-range shot well wide of the target.
Abraham went close once more not long after. A Cesar Azpilicueta header across goal came to the England international, who was unable to poke the ball home, signalling the end of the his day as he was substituted immediately after.
And, with the game seemingly petering out for a goalless draw, Hayden ensured Newcastle took all three points and their first victory of 2020.
Chelsea stay in fourth place, five points ahead of fifth-placed Manchester United, who have a game in hand, while Newcastle move up to 12th.