Cardiff's lead at the top of the npower Championship was cut to five points by Hull after the Bluebirds were beaten 2-0 by Brighton.
While the Welsh side were going down to only their second home defeat of the season, Hull beat Blackburn 2-0. Other notable results saw Wolves drop into the relegation zone following defeat at Barnsley.
Jose Ulloa whipped in a cross which found Andrea Orlandi in front of goal and he flicked the ball home with the outside of his foot.
The Bluebirds enjoyed greater possession and hit the woodwork four times but it was the Seagulls who breached their opponents' defence when Ulloa pounced in injury time.
Hull claimed their third successive victory to cut the gap at the top. The Tigers went ahead in the 52nd minute when Stephen Quinn hooked the ball in from the edge of the area and found Mohamed Gedo who slotted home a low shot from close range.
Hull doubled their lead (67) when Quinn raced down the left-hand side, before checking back to send in a right-footed cross which found Ahmed Elmohamady and he volleyed home.
Watford maintained their challenge with a 2-0 win at Ipswich to remain third, while Charlton put a dent in Leicester's challenge when they won 2-1 at the Foxes.
Radoslaw Majewski scored a first-half hat-trick as Nottingham Forest eased to a 6-1 win over Huddersfield who are slipping closer to the drop zone as Barnsley and Wolves traded places in the relegation zone after the south Yorkshire side came from behind to win 2-1.
Peterborough climbed off the bottom with a 5-1 win at 10-man Millwall, while Derby and Bolton drew 1-1.
Crystal Palace remain fourth after a 2-1 win over Bristol City, who are now bottom of the table.