Saints lost two-one away to Spurs this afternoon following a long range Christian Eriksen goal and a Dele Alli penalty.
James Ward-Prowse got one back for the visitors early in the second half, who could not chase down Spurs who were more professional on the day.
Southampton were on the back foot from the off, with Fraser Forster racing off his line to deny Son Heung-min early on. The South Korean was fed by a wonderfully weighted pass from Eriksen down Saints' left with the England stopper making himself big.
And it was the Danish midfielder who opened the scoring, drifting onto Mousa Dembele's pass and moving infield unopposed. He bent a delicious finish inside the far post with Southampton failing to close down the home team.
The visitors looked well off the pace in the first half, and Spurs were in no mood to let them back into the game. Oriol Romeu hit a nice half volley just wide off of Toby Alderweirald, and Manolo Gabbiadini curled a crisp first time effort just wide of the post following an excellent one-two with Dusan Tadic.
Then followed a disastrous few minutes for the visitors. Gabbiadini, who has been in great form since arriving in January, limped off after pulling his groin to be replaced by Shane Long 30 minutes in. The ball then went down the other end with Spurs scoring the second in fortuitous circumstances.
Saints failed to clear the danger a couple of times with players getting in each others' way. The ball fell to the edge of the box and Alli just nicked in ahead of the onrushing Steven Davis. Alli did well to earn a penalty, wrapping his leg into Davis' who could have little complaint. Alli then stepped up to stroke the penalty to Forster's left with the goalie diving the other way.
Nothing went Southampton's way in the first half, with balls ricocheting off them by the touchline, bounces falling to the home side and inconsistent refereeing adding to the mix.
Tadic smashed a cutback way over the bar, with the linesman erroneously judging the ball to have gone out of play.
Just before the half way mark Saints looked to have fluffed a corner with their preferred short pass approach. Cedric Soares drove a powerful shot straight at Hugo Lloris, whose parry fell to Tadic in the box.
Tadic received the ball and was booted by Ben Davis, in almost identical fashion to that which saw Spurs awarded a penalty earlier - referee Andre Marriner though failed to award the foul and Saints limped in at half time feeling aggrieved and having been outplayed.
Saints emerged from half time a much improved team, taking the game to Tottenham and playing with more belief and penetration.
An early Eriksen effort aside, which flew wildly over the bar, the visitors looked energetic and creative in the second half.
They scored just a few minutes following the restart through Ward-Prowse. Nathan Redmond cut back a low cross which evaded the Spurs defence, with Ward-Prowse calmly controlling the ball and sliding it past Lloris at the near post. Game on, with Saints' two wingers recently called up to the England squad combining.
Son nearly reestablished the lead seconds after, with the ball landing at his feet barely five yards from goal. Fortunately for Southampton, he couldn't get his feet sorted and the danger passed.
Shane Long was his usual self after coming on, harrying defenders and looking to use his pace in behind the Spurs' high line. The Irishman raced onto Davis' through ball and lashed a shot at Lloris from a tight angle. Southampton were looking dangerous.
Then came a period where Spurs slowed the game down with Saints frustrated. The visitors' tactic was plain to see - to break behind the aggressive defensive line - but they were rarely successful through poorly timed runs and several poor decisions from the linesman.
Sofiane Boufal replaced Tadic just before the 70 minute mark, and put in a woeful display, wasting several promising opportunities by overplaying and surrendering possession.
Jay Rodriguez, on for Nathan Redmond with ten minutes left, looked bright though, beating the offside trap and showing great technique in controlling a difficult ball before having it pinched off him in the box.
Saints continued to pressurise spurs, but were found wanting with Alli and Vincent Janssen passing up chances to end the encounter late on. The home side managed the latter stages of the tie well, earning their tenth consecutive home win in their final season at White Hart Lane.
For Southampton, the team looked a little short following the break having not played for over two weeks. Next up are Bournemouth on April 4th, with Southampton aiming to finish the season strongly if they are to finish inside the top ten once more.
Spurs: Lloris (c); Vertonghen, Dier, Alderweireld; Walker (Trippier 78), Dembele, Wanyama, Davis; Alli, Eriksen (Janssen 85); Son (Winks 74).
Subs: Vorm, Trippier, Wimmer, Onomah, Sissoko, Winks, Janssen.
Saints: Forster; Cedric, Stephens, Yoshida, Bertrand; Ward-Prowse, Davis (c), Romeu, Redmond (Rodriguez 80), Tadic (Boufal 68); Gabbiadini (Long 32).
Subs: Long, Rodriguez, Caceres, Boufal, Hojbjerg, McQueen, Hassen.