Brighton stunned Graham Potter with a 4-1 mauling of his Chelsea side on his return to his former club.
Leandro Trossard continued his run of scoring in every game under Roberto De Zerbi with the opener after five minutes, and Ruben Loftus-Cheek turned a corner into his own net nine minutes later to put the visitors in a big hole.
De Zerbi was chasing his first victory as Brighton boss, and he appeared to have gotten his tactics spot on with a surprise switch to a back four.
Brighton were threatening every time they went forward, and only two heroic clearances from Thiago Silva kept the score down.
Just before half-time though, Brighton got their third after Pervis Estupinan raced down the left and fizzed a ball into the near post. Trevoh Chalobah got the final touch, but Japan winger Kaoru Mitoma would have scored if the Chelsea defender hadn’t.
Kepa was replaced by Edouard Mendy at half-time, with the Spanish goalkeeper apparently suffering an injury.
Chelsea needed to start fast in the second half and they did just that when Kai Havertz drifted away from his defender to head home Connor Gallagher’s excellent cross.
The match was on a knife-edge, but Brighton held fast and continued to threaten on the break.
Brighton’s Paraguayan teenager Julio Enciso was thrown into the mix and immediately caused Chelsea trouble with his pace and energy.
The Blues continued to press but the home side held on and added a fourth late on through Pascal Gross for their first ever league victory over Chelsea, and their first in all competitions since 1933.
TALKING POINT – HAVE BRIGHTON PROVIDED THE BLUEPRINT TO BEAT CHELSEA?
The Seagulls overwhelmed Chelsea with energy in the first half but they also showed the weaknesses in Graham Potter’s usual set-up.
They exploited the space in behind the Blues’ wing-backs by first passing into midfield before moving the ball out wide. Time and again it resulted in dangerous attacks.
Chelsea are obviously fatigued after a midweek Champions League fixture, and Brighton were highly motivated, but they may have also shown other teams the way to win.
PLAYER OF THE MATCH
Virtually every Brighton player could have been named player of the match at half-time, but Leandro Trossard was a cut above. The Belgian took his goal well but also showed maturity and leadership which his team needed in the tougher moments.
He had six shots, all from inside the box, and also contributed in the build-up. An excellent display among excellent displays.
Brighton: Sanchez 7, Webster 6, Estupinan 7, Dunk 7, Caicedo 7, Mac Allister 7, Trossard 8, March 7, Lallana 6, Mitoma 8, Gross 7. Subs: Enciso 7, Lamptey 6, Sarmiento N/A
Chelsea: Kepa 4, Silva 7, Cucurella 5, Chalobah 4, Kovacic 6, Loftus-Cheek 7, Gallagher 7, Sterling 6, Havertz 5, Pulisic 4, Mount 6. Subs: Broja N/A, Mendy 5, Ziyech N/A, Aubameyang 6, Chilwell N/A
5’ GOAL BRIGHTON Mitoma races into the box and slips a clever ball to Leandro Trossard who dances into space and places his shot into the bottom corner.
14’ GOAL BRIGHTON Ruben Loftus-Cheek turns the corner into his own net. Brighton are playing like a team possessed, and Chelsea have been overwhelmed early.
42’ GOAL BRIGHTON Estupinan races into space down the left and rolls his cross towards Mitoma. It looks like Chalobah got the final touch.
48’ GOAL CHELSEA Havertz drifts away from his man in the box and heads the Connor Gallagher cross beyond Sanchez to give Chelsea a lifeline.
90’ GOAL BRIGHTON Julio Enciso smashes two shots at Mendy that he can only parry before Pascal Gross finally puts it away.