For the second time in less than a week, Chelsea travelled to Brighton & Hove Albion and left empty-handed, following up their FA Cup defeat last weekend with a deflating Premier League loss.
Going into this double-header Brighton had been thrashed 7-0 at Nottingham Forest and Chelsea had earned a much-needed win over West Ham United, but Enzo Maresca's side will now be grateful they do not have to return to the Amex Stadium again this season.
The visitors began brightly enough but they lost Noni Madueke to injury and then another winger, Brighton's Kaoru Mitoma, stole the show with a sublime goal to put his side ahead.
He beautifully controlled Bart Verbruggen's long pass forward, beat his marker and curled the ball beyond Filip Jorgensen.
Yankuba Minteh doubled the home side's advantage later in the first half, his composed finish coming after smart approach play from Georginio Rutter.
Chelsea never really threatened a comeback and went further behind when Minteh scored his second midway through the second half, capitalising on slack defending from the visitors to cut in from the right and drill home a low shot.
The defeat, one of Chelsea's worst performances of the season, means they stay fourth in the Premier League table. Brighton move up to eighth, six points behind them.
Simon Johnson and Anantaajith Raghuraman analyse the main talking points.
If Maresca thought losing to Brighton in the FA Cup was bad, this humbling in the Premier League against the same opposition just six days later was a lot worse.
The Italian had almost a full week to work on things in training to generate a better performance and game plan, but this was an even bigger disappointment.
Yes his side are missing some key players right now, particularly in the striker department. However, Nicolas Jackson was on his longest goal-scoring drought at Chelsea before he sustained a hamstring problem at home to West Ham last week.
Maresca put himself under more pressure from Chelsea fans to win this game by saying after the FA Cup loss that going out of the competition could be a positive for their Premier League campaign. Well, it did not look like it on this evidence.
Chelsea offered no real threat and defensively they were all over the place too, conceding three goals that you would normally see from a bottom-four side rather than one that currently sit fourth in the table.
Maresca showed his frustration on a regular basis, throwing his arms up in the air on more than one occasion. But after Chelsea extended their winless away run to five Premier League games (six in all competitions), Maresca looks like a man struggling to think of ways to turn the slump around.
Having Brighton supporters sing 'can we play you every week?' said it all.
Simon Johnson
Chelsea's bad run of form has coincided with players suddenly going down with injury and Madueke has become the latest victim.
Maresca's side actually made a reasonable start at Brighton, with Madueke causing more threat down Chelsea's right flank than Pedro Neto managed in the FA Cup defeat last weekend.
The score was still goalless when he broke clear and passed for Cole Palmer to shoot. The latter wasted it by sending his effort well wide but the consequence of the move was far worse than that as Madueke went down with a suspected hamstring problem and had to be replaced.
Madueke's departure meant Maresca had to switch Neto from the left wing to the right, with Jadon Sancho coming off the bench to play where Neto was operating. Chelsea's threat from wide was negated a lot more easily by Brighton from this point.
Chelsea are already without Wesley Fofana, Romeo Lavia, Benoit Badiashile, Jackson and Marc Guiu until April and Madueke is surely facing a similar time on the sidelines.
All these players have picked up their respective injuries over the past two months, a period in which Chelsea have gone from being the second-best team in the Premier League to winning just two of their past nine top-flight games.
There was a further blow for Maresca when Malo Gusto had to be replaced in the second half, soon after needing treatment for what looked like an injury to his left hip.
Simon Johnson
Brighton followed a similar strategy to the one they used in the FA Cup on Saturday, restricting Chelsea's options down the middle.
Carlos Baleba and Jack Hinshelwood, with help from Mitoma and Rutter, shut down any passes through the lines in the centre of the pitch. The absence of a ball-carrying, progressive midfielder clearly hurt Chelsea. Palmer repeatedly tried to drop deep in the centre to assist with their build-up, but that rarely helped, leaving Chelsea light further up the pitch instead.
That forced the visitors out wide and early on, there were signs that it could work when Christopher Nkunku dropped on the right and combined with Madueke to create two decent opportunities for Palmer, which he blazed over the bar. But after Mitoma's opener, Brighton limited those opportunities too.
At the start of the second half, Nkunku drifted over to the left and a similar pattern followed, but Brighton dealt with it well, with the lack of incisive passing in the central areas of the pitch hurting Chelsea again. When they did attempt a brave pass through the middle early in the second half, Baleba intercepted it and got a shot away.
Chelsea enjoyed almost 70 per cent possession on the night -- much more than the 58 per cent they recorded on Saturday -- but did precious little with it again. In fact, they did not manage a single shot on target, the first time that has happened under Maresca (and something that did not happen at all under Mauricio Pochettino last season).
Anantaajith Raghuraman
We will bring you this after he has spoken at the post-match press conference.
Saturday, February 22: Aston Villa (A), Premier League, 5.30pm GMT, 12.30pm ET