Christian Eriksen scored in each half to cancel out the visitors' two-goal lead, with Jay Rodriguez and Adam Lallana both netting, before the Icelander's stunner claimed victory
The hosts' high line looked perilous from the off, with the linesman's flag denying Jay Rodriguez an early goal, but the England international was not to be shut out for very long, latching onto a high ball forward to stroke the ball beyond Hugo Lloris and into the bottom corner.
A defensive mix-up from Kyle Naughton gifted possession to Saints deep in Tottenham's half, with Adam Lallana punishing the error with a clinical finish to double the lead. Spurs halved the deficit quickly, though, with Eriksen prodding in at the far post from a low cross.
|VIEW FROM WHITE HART LANE
|By Tim Poole
It is not like Tim Sherwood to do things the easy way, is it? The Tottenham boss insisted he would spend the first part of the game in the stands and, during that time, a superb Southampton side went 2-0 up after wonderfully worked goals from Jay Rodriguez and Adam Lallana.
But Spurs - and Christian Eriksen particularly - came back with a bang. The Dane struck not once but twice to draw the home side level, with Sherwood's half-time team talk clearly working wonders; Spurs were terrific after the break.
And, in the end, it was Sherwood's super-sub Gylfi Sigurdsson who won the game with a terrific injury-time strike. Both for good and for bad, then, Sherwood was instrumental today.
There were signs of life from Sherwood's men on Thursday night as they threatened a stunning turnaround before ultimately losing 5-3 on aggregate to Benfica to exit the Europa League, a disappointment that followed defeats to Chelsea and Arsenal.
Yet any confidence gleaned from that performance in Lisbon was not in evidence during a nervy and open start as Tottenham afforded their opponents too much space – although that was not the contributing factor when the visitors were gifted an opener.
Naughton completely misjudged the simplest of headers from Boruc's goal kick, paving the way for Rodriguez to race clear and curl home his third goal in as many games.
Things quickly went from bad to worse for Naughton, too, as another failed clearance by the full-back fell to Rickie Lambert, whose silky close control and simple ball enabled Lallana to slot past Hugo Lloris.
Nathaniel Clyne then continued the theme of errors from right-backs, allowing Tottenham back into the game; the former Crystal Palace man completely fluffed his lines attempting to clear Nabil Bentaleb's cross and Eriksen was on hand to side-foot past Boruc.
The frenetic nature of the game showed no signs of halting before half-time as Rodriguez and Eriksen both spurned good chances.
The half-time break did little to dull proceedings either, with Tottenham equalising within a minute of the restart.
Roberto Soldado stole the ball from Dejan Lovren on the right wing, cut inside and slid across to Eriksen – who made no mistake with the goal gaping.
Southampton completely lost their early verve as Tottenham piled forward with increased fluency in search of a third goal to end their current slump.
When Nacer Chadli hit the side-netting it appeared as though a point would have to suffice for both Tottenham and outspoken boss Sherwood, only for Sigurdsson to win the game with a stunning strike that glided into the bottom corner to keep Spurs' slim top-four hopes alive.