London - Tottenham Hotspur manager Mauricio Pochettino insisted he always trusted Dele Alli's talent despite the England international's struggles to meet his high standards this season.

Alli doubled his tally for 2018 by scoring twice in four second-half minutes as Spurs beat Chelsea 3-1 on Sunday to end a 28-year wait for a Premier League win at Stamford Bridge.

Defeat for the hosts all but ends Chelsea's hopes of Champions League football next season as Spurs opened up an eight-point lead over their closest challengers for fourth place.

"I'm very, very pleased for Dele," said Pochettino. "It's been a tough period for him, but I like his talent, his character. I'm so happy for him because he deserved it."

Alli was left out of both England's recent friendlies against the Netherlands and Italy with Gareth Southgate suggesting his place in the starting XI at the World Cup was far from secure.

"I'm sure people will still be disappointed with the way I played today," said Alli, who celebrated his first goal provocatively in front of the Chelsea fans. "I don't think I had to prove (anything) with the way I played today."

But after scoring 22 goals last season, Pochettino believes Alli has just become a victim of his own success so early in his career.

"In the end, he's a great talent, only 21 years old, and sometimes we lose the focus on that. He's only 21. Sometimes the expectation is too much."

Spurs' performance was even more impressive as they came from behind after a huge error from captain and goalkeeper Hugo Lloris gifted Alvaro Morata the opening goal.

Christan Eriksen's wonder strike levelled in first-half stoppage time, before Alli took centre stage to end a barren run by his standards with two smart finishes just after the hour mark.

"When we were down against Chelsea, the team showed great quality and deserved the victory," said Pochettino. "We are in a good place to achieve the top four, and to do that at the end of the season is the challenge."

Spurs could even afford the luxury of doing the damage without Harry Kane, who made his return from a three-week layoff with ankle ligament damage 16 minutes from time.

Chelsea manager Antonio Conte's days in charge look numbered as failure to make the top four is likely to seal the Italian's fate no matter what comes of their run to the semi-finals of the FA Cup.

"My task is to work, and I know that I and my staff work 24 hours a day for Chelsea," said Conte.

"Then the club has to take the decision. I am not worried about this."

Conte has consistently complained of his lack of input over transfer dealings this season and insisted he has got the most out of a squad that won the Premier League at a canter last season.

"Yeah, I'm sure about this. We are working very well, very hard and the commitment of the players is top. Despite this if you stay in this position you must be a bit worried," added Conte.

Chelsea enjoyed most of the chances before the break, but needed Lloris's help to open the scoring.

Morata hadn't scored in the Premier League since Boxing Day, but no one has scored more headed goals in the league this season and he was left with the easiest of tasks to nod into an empty net as Lloris flapped at Victor Moses's cross.

However, Chelsea couldn't hold their lead until the break as in first-half stoppage time the ever dangerous Eriksen took aim from 25 yards and his fierce dipping effort clipped the bar on its way past Willy Caballero.

Just after the hour mark Spurs then led when Alli brilliantly controlled Eric Dier's long pass before slotting inside Caballero's near post.

Alli soon had a second as Spurs set the seal in a hugely symbolic win.

Son Heung-min was twice denied by Caballero but Alli pounced on the pinball inside the Chelsea area before slotting into the bottom corner.