All the talk before the game was about the Welshman, who on Thursday added the Football Writers' Footballer of the Year award to the Professional Footballers' Association Player of the Year and Young Player of the Year awards he won last week.
But it was a first half to forget for Bale and Tottenham as they were outplayed for large periods by Southampton.
The excellent Nathaniel Clyne had the visitors' first chance when he found himself clean through on the right but appeared to drag his shot wide of Hugo Lloris's goal.
Spurs then lost influential midfielder Mousa Dembele on 35 minutes with what looked like a hamstring injury.
Lewis Holtby came on in place of the Belgian and could only watch as Rickie Lambert's free-kick was expertly tipped onto the post by Lloris. Steven Davis was quickest to react to the follow-up but his header was tame and straight at the French goalkeeper.
Tactically Mauricio Pochettino's side got it spot on during the first period and prevented Spurs from having any notable attempts at Artur Boruc's goal.
The second half started in pretty much the same fashion. Spurs struggled to get a grip on the game and Adam Lallana tricked Michael Dawson before firing at Lloris.
As the game reached the closing stages Emmanuel Adebayor was sent on in place of Clint Dempsey and, when the Togolese forward sent Bale free, it appeared the home side may claim their first penalty at home for two years but referee Mark Clattenburg waved away the Spurs players protests.
Then, on 86 minutes, Bale illuminated what was largely a forgettable game. Picking the ball up on the right wing from Kyle Walker he cut inside before unleashing a sensational shot past Boruc and into the bottom corner.
It wrapped up a remarkable week for Bale and kept alive his side's hopes of playing Champions League football next season.