Flynn Downes' goal in the final seconds gave Southampton a dramatic victory over Watford and kept them in with a chance of automatic promotion.
Watford came back from two down after Will Smallbone's goal inside the first minute gave the hosts the perfect start and Che Adams doubled their lead.
Ryan Porteous' deflected strike reduced the deficit and Ismael Kone's late equaliser appeared to have rescued a point for the Hornets.
But Downes netted in the ninth minute of stoppage time, leaving the fourth-placed Saints seven points behind second-placed Leicester but with a game in hand, and having played two fewer matches than third-placed Leeds.