James Maddison after bagging Spurs' fifth
Tottenham ran riot on the south coast with James Maddison on target twice to earn Ange Postecoglou a much-needed Premier League victory by a 5-0 score, which only increased the pressure on Southampton head coach Russell Martin.
Spurs were winless in five ahead of this clash at St Mary's and without nine players, but scored three times inside 14 minutes.
Maddison started the rout after 36 seconds before captain Son Heung-min and Dejan Kulusevski struck in quick succession.
The Saints' faithful could have been forgiven for getting flashbacks of the 9-0 loss to Leicester in 2019 and turned their anger on under-fire Martin.
Postecoglou's men were not finished there, with Pape Sarr able to grab a fourth in the 25th minute before Maddison added another in first-half stoppage-time.
It failed to stop Tottenham's noisy away support repeatedly calling for chairman Daniel Levy to leave the club, but this result - on the club's first return to Southampton since Antonio Conte's extraordinary rant in 2023 - moved them within four points of fifth-placed Manchester City.
This was a battle between two head coaches wedded to their attacking philosophy but in desperate need of a victory and Postecoglou handed first league starts to Djed Spence and teenager Lucas Bergvall.
Amid a poor run of form, discontent amongst the Tottenham fanbase had grown with frustration aimed at chairman Levy and chants for him to leave occurred immediately after kick-off.
However, 36 seconds later and Spurs' travelling support had a goal to celebrate when Maddison fired them in front.
Spence was the architect as he twisted away from Flynn Downes and played through to Maddison, who fired under the fit-again Alex McCarthy in the Saints goal.
More chants of 'Levy out' followed before Tottenham made it 2-0 in the 12th minute.
Again Maddison was involved with his deep cross flicked on to Son at the back post and the Spurs captain rifled home his 13th goal against Southampton.
Pape Sarr was amongst the scorers for Tottenham
The home supporters had already turned on Martin by this stage, but worst followed two minutes later when the visitors grabbed a third.
Son's cross was only partially cleared by Jan Bednarek and Kulusevski was first to the loose ball to fire home for 3-0.
It was turning into a nightmare experience for Martin with Southampton fans singing he would be 'sacked in the morning' and he responded by bringing off Kamaldeen Sulemana.
Sulemana was not happy and tried to engage with Martin on the touchline, but it failed to stem the tide as Tottenham claimed a fourth in the 25th minute.
More good work by Son saw him pass into Sarr, who twinkle-toed past substitute Nathan Wood and slid the ball home.
Postecoglou's joy dampened slightly when left-back Destiny Udogie limped off before the hosts should have pulled one back five minutes before half-time but Adam Armstrong sent an effort wide following Ryan Manning's cross.
A small section of Southampton supporters had already headed for the exit and Martin walked down the tunnel with a minute of first-half stoppage time left, which meant he missed Spurs' fifth goal.
Son produced a sublime pass with the outside of his boot and Maddison cut inside Mateus Fernandes before he arrowed into the top corner.
It was Son's last involvement as he was replaced at half-time with Thursday's Carabao Cup last-eight tie with Manchester United in mind.
Armstrong fizzed an effort wide soon after for Saints but, predictably, the second half was played at a more pedestrian pace.
Kyle Walker-Peters, Wood and Tyler Dibling went close for Southampton before Mateus Fernandes headed in with 11 minutes left, but it was ruled out for offside as Tottenham consigned the league's bottom club to a heavy loss