Leeds United’s winless run extended to five games after a woeful first half at the Amex Stadium.
Brighton stepped up their automatic promotion challenge with a pulsating first-half display which earned them a 4-0 home win.
Israel striker Tomer Hemed was twice on target, including a penalty, as the fourth-placed Seagulls scored four times in the space of 20 minutes.
Poor defending contributed to United’s downfall as Brighton clinched a fourth successive home victory before a crowd of 25,150 at the Amex Stadium, and only two points now cover the top four sides in the Sky Bet Championship.
Albion cruised to victory in the second half and substitute Jiri Skalak should have added a fifth three minutes from time after surging into the area.
Afterwards, Leeds assistans manager Paul Raynor said: “It was simply shambolic. The manager is in there dissecting it.
“We can’t stand there in front of that watching that. Unacceptable and certainly unacceptable for Leeds United.”
Brighton defender Liam Rosenior received an early booking for bringing down the onrushing Lewie Coyle and midfielder Alex Mowatt put the resultant free-kick over the bar.
Rosenior gave away another free-kick shortly after when his high boot caught Coyle in another challenge, but the Brighton man escaped without punishment.
The Seagulls broke the deadlock when Hemed struck from the penalty spot in the 18th minute.
Midfielder Scott Wootton was penalised by referee Peter Bankes for pushing Rosenior as he cut inside and Hemed stepped up to steer the ball home from the spot to the left of keeper Marco Silvestri.
Silvestri pushed a goal-bound shot from Beram Kayal around the post before Brighton doubled their lead through striker Sam Baldock in the 22nd minute.
A mistake by skipper Sol Bamba allowed Baldock to storm through the middle and, after an exchange of passes with Dale Stephens, Baldock scored for the second successive match with a toe-poke that deflected off defender Liam Cooper.
It got worse for Leeds as Hemed had time and space to slot Brighton’s third in front of the Leeds supporters after Bamba, under pressure from Anthony Knockaert, failed to clear a long pass.
Leeds, who went into the game with just one win from their previous 10 Championship matches, had Mowatt cautioned for a late challenge on Hemed as the hosts dominated.
Albion’s pressure was further rewarded seven minutes before the break when central defender Lewis Dunk rose powerfully at the far post to head in a corner from Stephens.
Leeds had a let-off shortly after the break when former Charlton midfielder Stephens narrowly failed to get on the end of a teasing cross.
United’s 1,522 travelling fans, who never stopped backing their team with chants of ‘We all love Leeds’, almost had something to cheer about when a free-kick by Mowatt was deflected over after the Leeds midfielder had been brought down by Stephens.
Mowatt, carrying United’s chief threat, failed to draw a save from Albion keeper David Stockdale when he broke dangerously in the area and wastefully shot over from 12 yards.
United, now without a win in five league games, had more second-half possession and Frenchman Souleymane Doukara should have done better when shooting wide with only Stockdale to beat.