It couldn't come any sweeter as it came against their rivals Crystal Palace, who before tonight had a run of three successive wins.
The Seagulls fetched 3,300 fans to boost Palaces biggest crowd of 2005. How their fans will enjoy the journey back to the South Coast.
Mark McGhee's lads deserved their three points as they worked hard in every department and frustrated Palace with tight marking and deep defending.
The first half was a sorry affair with Michael Hughes missing a golden opportunity to fire Palace in front on 17 minutes, but after taking Clinton Morrison's pass in his stride he shot too close to the keeper who just managed to block away the shot.
Immediately at the other end Sebastien Carole was put clear following Leon Knight's throughball, but he lobbed over with just Gabor Kiraly to beat.
Substitute Alex Frutos and Carole kept Kiraly busy with further shots and Jake Robinson fired over on the stroke of half-time.
The second half offered little to cheer about until the 79th minute when Brighton had the last laugh and Palace stopped.
Knight had already shot wide of an open goal when shortly after Brighton forced another corner. Carole floated over the kick which Kiraly misjudged after leaving his goal.
Emmerson Boyce was outjumped by McShane whose precise header dropped neatly over the Hungarian keeper and into the empty net.
Palace never recovered although Morrison had the ball in the net in added time. Substitute Jon Macken fired a shot from 15 yards which was spilled by Wayne Henderson in the Brighton goal.
Morrison roared in to score, but the referee's assistant then put his flag up. Palace could not believe it, but at the end Brighton deserved the win.