Matty Fryatt answered his weekend critics to put the Foxes two goals to the good and looked to be sailing to another away win.
But, Micky Adams and his resilient Seagulls fought back to earn a shock win over City, who have now earned just three points in their last four matches.
Two well taken strikes from Fryatt fired the visitors into a comfortable two goal lead at the break.
And, on 58 minutes Fryatt was hacked down in the penalty area, but referee Keith Hill awarded a goal kick to the home side, a wrong decision that proved to change the outcome of the tie.
City Suffer Shock Defeat
Just one minute later Brighton were thrown a life line when Johnson smashed the ball towards goal from 25 yards out, the ball struck Kisnorbo and bounced past Martin to reduce the gap to just one goal.
Brighton began to control the game and had a hatful of half chances, With Virgo going closest but the Foxes looked like hanging on to their advantage.
But, with six minutes left on the clock, Johnson repeated his magic, with another piledriver from long range, flying past Martin.
A dissapointing night turned into a disaster four minutes later, when Jack Hobbs turned the ball cruelly into his own net, surrendering all three points to Micky Adams and his struggling Brighton.
The Foxes have fallen to sixth in the League One table and a backlash from the City Boo Boys looks inevitable.
Brighton began to control the game and had a hatful of half chances, With Virgo going closest but the Foxes looked like hanging on to their advantage.
But, with six minutes left on the clock, Johnson repeated his magic, with another piledriver from long range, flying past Martin.
A dissapointing night turned into a disaster four minutes later, when Jack Hobbs turned the ball cruelly into his own net, surrendering all three points to Micky Adams and his struggling Brighton.
The Foxes have fallen to sixth in the League One table and a backlash from the City Boo Boys looks inevitable.