Goals from Andy Carroll, Pedro Obiang and Mark Noble inspired West Ham to a comeback 3-1 win at Southampton as Slaven Bilic's men climbed into ninth in the Premier League.
A debut goal for Manolo Gabbiadini had Southampton fans in raptures, but celebrations were short-lived as West Ham responded with a trio of goals to bounce back in style from the 4-0 defeat at the hands of Manchester City on Wednesday.
Gabbiadini struck a 12th-minute opener, thundering the ball beyond West Ham goalkeeper Darren Randolph after he was found by a lofted Jay Rodriguez pass.
The former Napoli forward had little time to enjoy his moment, though, as Carroll levelled just two minutes later with a tidy finish under a despairing Fraser Forster.
West Ham put themselves into the lead on the stroke of half-time, Obiang netting his first goal for the club with an emphatic low strike from 25 yards to complete a first-half turnaround.
A deflected Mark Noble free-kick settled the game early in the second half to send Claude Puel's men slumping to a sixth loss in seven league games.
West Ham started brightly and a Sofiane Feghouli cross was headed just over by Carroll before referee Graham Scott awarded a free-kick for a push on Cedric Soares.
Gabbiadini opened the scoring for Southampton in emphatic style after just 12 minutes. The Italian beat West Ham's offside trap to latch on to Rodriguez's chipped pass before smashing the ball above Randolph.
West Ham responded almost instantly, as Carroll netted his fourth goal in as many games. The big striker evaded young Southampton defender Jack Stephens and was found expertly by Obiang before slotting past Forster.
Aaron Creswell tested Forster with a well-struck half-volley, as Cheikhou Kouyate's cross evaded the majority of the players in the box before reaching the former Ipswich Town full-back.
Rodriguez played a neat one-two with Sofiane Boufal before driving into the West Ham penalty area, though he saw his cross cleared comfortably by the returning former Southampton captain Jose Fonte.
It was 2-1 when Obiang struck from distance just before the half-time whistle, Southampton's clearance from a corner landing at the feet of the Spaniard, who struck decisively.
Half-time replacement Nathan Redmond won a free-kick in an inviting position for James Ward-Prowse, who whipped the ball over the West Ham wall to draw an agile save from Randolph.
West Ham extended their lead after 52 minutes as Noble took charge of free-kick duty. The Hammers captain drilled the ball towards the Southampton goal and a Steven Davis deflection left Forster helpless.
Prior to the hour mark Gabbiadini had a golden opportunity to get Southampton back into the game. A clumsy Kouyate header fell at the feet of the Italian, who lost his cool and blasted over.
The fingertips of Randolph were required to tip a Ward-Prowse header over after the midfielder was picked out by Cedric's searching cross.
Looking to atone for his part in West Ham's third goal, Davis struck ferociously from range, but was unable to beat the superb Randolph.
Michail Antonio almost added another goal for the Hammers in injury time, his driven strike flashing narrowly wide of Forster's far post.