It had all started so well for the Blues, who were in control throughout the opening 45 minutes and deservedly went into the half-time interval ahead after Enzo Fernandez headed home from close range via a deflected Reece James cross.

However, five minutes after the restart, a poor back pass from Andrey Santos enabled Diego Gomez to break forward toward our goal before going down under pressure from Chalobah. After a VAR review, the Blues defender was sent off.

It took some time, but Brighton made their man advantage count. Danny Welbeck levelled the score with a close-range header in the 77th minute and, in stoppage time, Maxim De Cuyper put the visitors ahead. Welbeck added a third in the final minutes to round off the scoring.

Starting brightly

Maresca made seven changes to his side. Robert Sanchez returned in goal after serving his one-game suspension, James and Marc Cucurella reclaimed the full-back roles, Moises Caicedo was back in the Blues midfield, and Estevao Willian, Pedro Neto and Joao Pedro came into the attack.

There was a notable buzz around Stamford Bridge before kick-off, and that was reflected in the start made by the Blues. We moved the ball crisply and instantly probed the Seagulls' backline.

Bart Verbruggen had an early save to make as he was forced to scramble across goal and palm wide a free-kick from Fernandez. Cucurella then flashed an attempt narrowly wide of the Brighton goal from distance.

Verbruggen was worked again inside the opening 10 minutes. It was the turn of James to test the Brighton goalkeeper from a free-kick, which the Chelsea captain arched toward the top corner. Again, it was saved.

Brighton posed little threat to the Chelsea goal in the early exchanges. A ball flashed across the six-yard box by Yankuba Minteh and a free-kick whipped in from the left held by Sanchez was the extent of the visitors' threat.

Deadlock broken

In contrast, the Blues looked capable of opening up the Brighton backline. Estevao saw a couple of shots blocked from promising positions, but the opening goal arrived midway through the opening period.

Caicedo was given too much time in midfield to pick a pass, which he slipped beyond the Seagulls defence and into the path of James. The Chelsea captain's attempted cross clipped the leg of Kaoru Mitoma and bounced up over Verbruggen and into the path of Fernandez, who was able to crane his neck and head home.

There was little response from Brighton to our opener, and the Blues fashioned a half-chance to add a second on the counter, but Neto couldn't hit the target after bringing the ball forward 40 yards.

Come the half-time interval, the Seagulls hadn't mustered a shot on target. A Yasin Ayari free-kick that drifted harmlessly over the crossbar and a Lewis Dunk header that did the same were the best the visitors had offered.

A set-back

There was a scare early into the second period when James landed awkwardly while challenging for a header. The Blues full-back needed treatment but, thankfully, he was okay to continue.

Unfortunately, from the restart, a passage of play unfolded that resulted in Maresca's side being reduced to 10 men for the second consecutive Premier League game.

Possession was worked back to Santos who, under pressure from Mitoma, tried to feed the ball back to Sanchez. His pass lacked the requisite pace, though, and enabled Gomez to bear down on goal. He went down under pressure from Chalobah, but referee Simon Hooper waved away the Brighton appeals.

Then VAR intervened. Hooper was advised to go to the pitchside monitor and, after a lengthy delay, the decision was taken that Chalobah had denied a goalscoring opportunity and was dismissed. There were 37 minutes remaining.

Maresca responded by introducing Josh Acheampong for Santos, and Gomez blazed the resulting free-kick over for the visitors.

With adversity to overcome, the noise from the Chelsea supporters increased. Another change followed from Maresca soon after, as Malo Gusto replaced Estevao.

Mounting pressure

Brighton head coach Fabian Hurzeler brought on Brajan Gruda and Welbeck to up the pressure on the Blues' defence. The latter came close within five minutes of his introduction, as a Jan Paul van Hecke shot ricocheted into Welbeck's path. He turned and shot, but the ball bounced narrowly wide.

Unfortunately, from Brighton's next opportunity, Welbeck was far more clinical. The goal was excellently fashioned by Minteh, who nipped beyond Gusto and fired the ball into the six-yard box, where Welbeck was on hand to power a header home.

Maresca turned to his bench once more as Benoit Badiashile replaced Hato at centre-back and Romeo Lavia came on for Neto. The Blues' shape shifted to a 5-3-1.

Brighton increased their pressure on the Chelsea goal further and there was another stoppage after Gusto caught the head of stooping Minteh. No penalty was awarded, and that was the correct call after a VAR review.

A whole 11 minutes were added. In the second of those, Brighton went ahead. A corner was worked short before being clipped to the back post by Ayari. Mats Wieffer was unmarked and headed back across goal for De Cuyper to nod beyond Sanchez.

James tried to mount a response as he managed to collect a long pass, trick his way past Minteh into the box, where he went down under a challenge. The referee waved away our appeals for a penalty, though.

And, in the final moments, with the Blues trying to construct a move upfield, Brighton were able to intercept and Welbeck was put through to score his sixth goal in seven matches against the Blues.

What it means...

A second consecutive defeat, coupled with results elsewhere, has seen the Blues fall to seventh in the early Premier League table.

What comes next...

The Blues are back in European action in midweek, as we welcome Jose Mourinho's Benfica to Stamford Bridge on Tuesday.

The teams

Chelsea (4-2-3-1): Sanchez; James (c), Chalobah, Hato (Badiashile 80), Cucurella; Santos (Acheampong 54), Caicedo; Estevao (Gusto 63), Fernandez, Neto (Lavia 80), Joao Pedro
Chelsea substitutes: Jorgensen, Gittens, Garnacho, George, Guiu
Scorers: Fernandez 24
Booked: Cucurella 42, James 66, Badiashile 89, Sanchez 90
Sent off: Chalobah 53

Brighton: Verbruggen; Veltman (Wieffer55), Van Hecke, Dunk, Kadioglu; Baleba (Gruda 67), Ayari; Minteh, Gomez, Mitoma (Welbeck 67); Rutter
Brighton substitutes: Steele, Boscagli, Coppola, Milner, Tzimas
Scorers: Welbeck 77, 90+10, De Cuyper 90+2
Booked: Veltman 9, Wieffer 64, van Hecke 89, Dunk 90, Welbeck 90+11

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