Albion have removed another rival from the fight to finish in the play-offs.
A 1-0 defeat for Ipswich at promoted Burnley today means Mick McCarthy's side cannot catch the Seagulls.
They are four points adrift with a game to go.
Former Albion striker Ashley Barnes gave his old club a helping hand. He initiated the move which led to Michael Kightly's 54th minute breakthrough for Burnley.
Bournemouth dropped out of the race last night when Albion beat Yeovil 2-0 at the Amex.
Reading, last day hosts Nottingham Forest, Blackburn and Watford are now the only teams capable of finishing above the Seagulls. They are all in action in 3pm kick-offs.
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