ALAN Bennett was sent-off as Brentford crashed to a disappointing defeat at the Withdean.
Glenn Murray headed the opener on 33 minutes, before subs Adam Virgo and Nicky Forster wrapped up the points in stoppage-time as Brighton leapfrogged the Bees in the League One table.
The visitors had an early penalty appeal turned down when Charlie MacDonald appeared to be fouled in the box.
But Murray headed the hosts in front just after the half-hour mark when he beat Wojciech Szczesny to Elliott Bennett's free-kick.
The Bees had a lucky escape minutes later when Murray's shot caused a goalmouth scramble, but Inigo Calderon eventually blasted the ball over the top.
MacDonald went close for Brentford when Peter Brezovan denied him from close range, while substitute Lionel Ainsworth saw a long-range effort saved.
Marcos Paimter should've wrapped up the points for Brighton late on, but he somehow shot straight at Szczesny from four yards, while former Bee Forster blazed over when clean through.
Brezovan had to be alert to keep Gary Dicker's header from going into his own net, but Brighton sealed the points in injury-time when Virgo's header beat Szczesny .
Brentford's misery was completed in the dying seconds when Bennett was sent-off for a second booking for handball, and Forster fired home the penalty.
BEES: Szczesny, Foster, Phillips (Bennett h/t), Legge, Dickson, Wood (Ainsworth 62), O'Connor, Diagouraga, Weston, MacDonald, Strevens (Cort 78).