Brighton and Hove Albion lost narrowly at Stamford Bridge after two quick goals in a three-minute spell in the first half.
Enzo Fernandez opened the scoring with a header after Chelsea won a corner.
The former Albion loan player Levi Colwill also headed in from a corner just moments later.
At first glance, Billy Gilmour appeared to have made a stunning goal-line clearance but Colwill was credited with the strike.
The Seagulls battled their way back into the match through Facundo Buonanotte just before the break.
And, soon after, Conor Gallagher was sent off with a few minutes still to play before the half-time whistle went.
Fernandez got his second from the penalty spot midway through the second half after tangling with substitute James Milner.
Albion pulled back a late goal through Joao Pedro.
Then, right at the end, referee Craig Pawson consulted VAR after Levi Colwill appeared to handle in the box.
But Albion were denied a penalty and the final whistle followed shortly after.