Harry Kane and Dele Alli were on target for Tottenham.
Tottenham regained its five-point cushion over Chelsea in the race for Champions League qualification by beating Watford 2-0 on Monday, with Harry Kane netting the second goal to keep alive his chances of being the English Premier League top scorer.
Dele Alli opened the scoring at Wembley Stadium for Tottenham, which won for the first time in three league games and requires two wins from its final three matches - against West Bromwich Albion, Newcastle and Leicester - to seal a top-four finish.
When Kane turned in Kieran Trippier's cross in the 48th minute, the England striker moved onto 27 goals for the campaign - four fewer than Liverpool's Mohamed Salah. Kane has won the Golden Boot the past two seasons.
Chelsea looked like it would not be qualifying for the Champions League after losing to Tottenham at home on April 1, but has won its last three games to stay in contention in fifth place.
"They were creeping up on our backs so now we can look forward," Kane said. "It was important just to get the job done and ease that pressure."
Spurs needed a response after losing to Manchester City 3-1 then drawing at Brighton. And, helped by Watford goalkeeper Orestis Karnezis, they got one.
Karnezis fumbled a cross from Trippier and Christian Eriksen reacted quickest to pass the ball across to Alli, who took one touch and slotted home his shot from eight meters out in the 16th minute.
Tottenham goalkeeper Hugo Lloris saved well from Andre Gray, Abdoulaye Doucoure, and Richarlison as Watford posed problems on the counterattack.
And Kane virtually ensured there was no way back for the visitors soon after halftime. He miskicked an attempted shot off Son Heung-min's pass, but picked himself up to convert another searching center from Trippier moments later.
Jan Vertonghen struck the post with a header and Kane had a goal disallowed for offside as Tottenham threatened a third goal.
Overhauling Salah looks a tough job, but Kane finished last season with eight goals in his final three games and he is hoping for a repeat, despite looking sluggish in recent performances.
"I would have liked to play better over the last few games but the whole team would have liked to do that," Kane said. "I feel good, I feel sharp. I probably could have scored a couple more today. I'm looking forward to the last three games.
"Last year was an unbelievable end, but we'll see what happens. In my mind, I'm just trying to get to that 30-goal mark."
Tottenham moved to within one point of third-place Liverpool and has a game in hand.
