Former Östersund coach Graham Potter left Brighton for Chelsea in September, but judging by Saturday, there was no given change upwards in his career.
Alternatively, the 47-year-old is still not the perfect solution for the London team.
Brighton, with new coach Robert De Zerbi, made a shock start and lined up several hot scoring chances from the start.
Already in the fifth minute it paid dividends, when Leandro Trossard rolled in 1-0.
The half continued in the same fashion, but got even worse for Chelsea.
Two own goals, from Ruben Loftus-Cheek and Trevoh Chalobah, made it 3–0.
Kai Havertz cut back nicely just after the break, but Chelsea got no closer.
In extra time, Pascal Gross instead ended the scoring with his 4–1.
- We had an early deficit that we didn't quite manage to turn around.
It was extra painful at halftime, of course.
We will come back quite well in others.
But overall, Brighton should have all the credit, they played very well especially in the first half, says Graham Potter in the match interview afterwards.