Manchester City beat Everton to move fourth
Substitute Mateo Kovacic added a second in injury time on the stretch as Pep Guardiola's men climbed to fourth on the standings.
Manchester City remain on track to qualify for next season's Champions League after winning at Everton with two late goals.
An uninspiring contest looked to be heading for a drab draw before being brought to life with six minutes remaining when young full-back Nico O'Reilly stole in from close range to convert Matheus Nunes' cutback.
Substitute Mateo Kovacic added a second in injury time on the stretch as Pep Guardiola's men climbed to fourth on the standings, four points clear of sixth-placed Chelsea, who face neighbours Fulham on Sunday.
Brentford forward Bryan Mbuemo scored twice as the Bees dealt a blow to Brighton's hopes of qualifying for next season's European competitions.
The Cameroon international gave Thomas Frank's side the lead with a powerful right-footed effort following a defence-splitting Keane Lewis-Potter through ball.
Striker Danny Welbeck equalised for Brighton with his ninth league goal of the season - equalling his most prolific Premier League campaign - by heading in Mats Wieffer's cross on the stroke of half-time.
Mbuemo, 25, scored his second of the day and 18th of the season when his curling effort found the bottom corner after a slight deflection off Lewis Dunk.
The Cameroonian turned provider for Brentford's third, teeing up strike partner Yoane Wissa, who saw his effort deflect in after cannoning off defender Jan Paul van Hecke.
It went from bad to worse for Brighton as Brazilian striker Joao Pedro was shown a straight red card for lashing out at Brentford defender Nathan Collins in an off-the-ball incident.
The Seagulls set up a tense finish when substitute Kaoru Mitoma scored their second, beating Mark Flekken with a deft left-footed finish following Jack Hinshelwood's through ball.
But Brentford captain Christian Norgaard put the result beyond doubt in the sixth minute of stoppage time when he headed in Mathias Jensen's free-kick.
In other matches, West Ham drew 1-1 with Southampton at the London Stadium to continue their miserable form, while Crystal Palace and Bournemouth played out a barren draw at Selhurst Park in London.