Tottenham's winless run in the Premier League stretched to four games as Mauricio Pochettino's men threw away an early lead through Harry Kane to lose 2-1 at Southampton on Saturday. The Saints' spirited second-half comeback ensured they remain two points above the relegation zone despite Cardiff's 2-0 win over West Ham. Brighton also boosted their survival hopes thanks to Anthony Knockaert's brilliant strike to win 2-1 at Crystal Palace, while Newcastle battled back from 2-0 down to beat Everton 3-2.
Despite their poor domestic form of late, Spurs were boosted by victory at Borussia Dortmund in midweek to reach the quarter-finals of the Champions League.
But Tottenham are now in grave danger of missing out on Champions League football next season. Pochettino's side remain in third but their lead over Manchester United, Arsenal and Chelsea is a precarious one with all three chasers in action on Sunday.
Dele Alli made his return after seven weeks out with a hamstring injury and the England international duo combined to great effect for Kane's opener on 26 minutes.
Kane freed Alli in behind the Southampton defence and he then returned the favour to pick out the England captain at the back post, who controlled and slotted low past Angus Gunn for his 200th career goal.
However, Spurs wastefulness in failing to add to their lead came back to cost them as Southampton improved after the break and secured a vital three points in their attempt to beat the drop.
Fresh from scoring his first professional goal away to Manchester United last weekend, right-back Yan Valery levelled from Stuart Armstrong's cross.
James Ward-Prowse then completed the comeback with a stunning free-kick curled into the top corner to leave Hugo Lloris helpless.
Newcastle remain six points above the relegation zone and moved up to 13th thanks to a thrilling fightback of their own to beat Everton.
Dominic Calvert-Lewin put the visitors in front on 18 minutes before a moment of high controversy when Jordan Pickford pulled down Salomon Rondon.
A penalty was awarded, but the England number one was not sent-off and then saved Matt Ritchie's resulting spot-kick.
Richarlison soon put Everton 2-0 in front, but Newcastle struck three times in 19 second-half minutes through Rondon and Ayoze Perez's double for a deserved win.
Brendan Rodgers secured his first win as Leicester boss thanks to Jamie Vardy's second-half double to beat Fulham 3-1, who are now 13 points adrift of safety.
Huddersfield also look dead and buried as Bournemouth cruised to their first away win since October with a 2-0 victory at the John Smith's Stadium.
Callum Wilson opened the scoring on his return from a two-month injury layoff to aid his chances of making Gareth Southgate's England squad later this week before Ryan Fraser doubled the Cherries' advantage 24 minutes from time.
Cardiff, though, gave themselves hope as early goals in each half from Junior Hoilett and Victor Camarasa gave the Welsh side a precious three points over a hugely disappointing West Ham.
Brighton also secured a much-needed win to move level on points with rivals Palace, five above the drop zone.
Chris Hughton's side took the lead through Glenn Murray's early goal at Selhurst Park before Luka Milivojevic equalised with a second-half penalty.
However, Knockaert sparked wild celebrations from the Brighton fans when he curled into the top corner the winner 16 minutes from time.