A stoppage-time header from Aron Gunnarsson gave Cardiff City all three points against nine-man Watford this evening.
The Iceland international sealed the win, after Pete Whittingham's penalty kick had cancelled out Tommy Hoban's opportunistic opener.
Hoban tapped home against the run of play on 28 minutes, after goalkeeper David Marshall had failed to hold on to Matej Vydra's powerful header.
Daniel Pudil was shown a straight red card for violent conduct on 64 minutes.
Mark Yeates then handled inside the penalty area seven minutes later, allowing Whittingham to level the scores with a confident spot kick.
Watford's task was made even more difficult 17 minutes from time when Nathaniel Chalobah was shown a second yellow card for kicking the ball away.
The hosts' numerical advantage finally told with seconds remaining, when Gunnarsson nodded home from 12 yards following Craig Noone's whipped cross.
The Bluebirds remain level on points with league leaders Leicester City, who beat Brighton & Hove Albion 1-0 tonight.