Albion beat Peterborough 2-0, with goals from Craig Noone and Ryan Harley, to go top of English football’s second tier for the first time since 1979.
Earlier Albion were drawn at home to Liverpool in the 3rd round of the Carling Cup, shortly before they became the top side in the Premiership.
In front of an Amex crowd of just over 19,000 the Seagulls swept aside the Posh with Noone firing in the opener from the edge of the box after a miskick by the Peterborough keeper Paul Jones.
Moments earlier Noone had played in Ashley Barnes, who was unable to find the target.
Darren Ferguson’s side responded with efforts from Grant McCann and Paul Taylor but Casper Ankergren kept them at bay.
And with George Boyd going off injured ten minutes before half time, Ferguson could be forgiven for thinking that possession may be nine tenths of the law but that counts for little in a fortres home like Falmer.
For Peterborough held the ball more than Albion but couldn’t make it pay off.
And so soon after firing seven past Ipswich, the visitors were punished for their inability to finish what they started – and punished for a foul on Barnes by Tommy Rowe.
Harley, newly signed from top flight Swansea, stepped up for the free kick and marked his debut with a stunning 30-yarder which curled into the top corner of the Peterborough net in the 65th minute.
Craig Mackail-Smith almost added a third late on but his off-target header denied him the chance of making it on to the score sheet against his old club.
A determination not to let a two-goal lead slip again – and Peterborough’s lack of penetration – made for another three points to send the Falmer faithful home happy.
Albion: Ankergren; Calderon, Greer, Dunk, Painter; Dicker, Bridcutt, Harley; Barnes, Mackail-Smith, Noone. Subs: Brezovan, Cook, Dicker, LuaLua, Navarro, Sparrow.
Peterborough: Jones; Little, Bennett, Zakuani. Alcock; Frecklington, McCann, Boyd, Rowe; Taylor, Tomlin. Subs: Lewis, Ball, Gordon, Tunnicliffe, Wootton.
Ref: Gavin Ward (Surrey)
