Chelsea strengthened their grip on fourth place in the Premier League with victory over Tottenham in a bad-tempered game as Antonio Rudiger allegedly suffered racist abuse.
Brazil forward Willian opened the scoring when he cut in from the left flank and superbly curled the ball beyond the reach of Paulo Gazzaniga.
Willian added a second from the penalty spot shortly before half-time when the video assistant referee determined Gazzaniga had clattered Marcos Alonso after racing off his line.
Spurs were reduced to 10 men shortly after the hour mark when Son Heung-min was shown a straight red card for petulantly kicking out at Rudiger.
Chelsea goalkeeper Kepa Arrizabalaga was struck by a bottle thrown from the crowd while Rudiger gesticulated to suggest that he had been abused.
Spurs responded with three announcements over the public address system that stated racist behaviour was interfering with the game.
Chelsea’s victory – Frank Lampard’s second as a manager over his one-time boss Jose Mourinho – left them four points clear of fifth-placed Sheffield United while Spurs remain seventh.
The match appeared to be marred by racist behaviour from the crowd. Referee Anthony Taylor stopped the game in the second half after an object was thrown on to the pitch and he was approached by Blues defender Antonio Rudiger.
An address made over the public address system then warned “racist behaviour is interfering with the game”.
Second and third announcements followed with the game heading towards its end.
Uefa’s three-step protocol says that a game can be abandoned if fans have been warned twice before.
Speaking at the game, former Newcastle and Tottenham midfielder Jermaine Jenas said: “With the technology they have in this stadium, I would be shocked if they could not pinpoint the individual.
“That person will be isolated and dealt with accordingly. There is no place for it but I want more than an announcement.
“I do not want them back in the stadium ever again – sadly some people are that ignorant.”
A supporter was arrested and bailed over allegations of racist abuse against Manchester United players during their Premier League match at Manchester City on 7 December.
A video had been circulated on social media of a man appearing to make monkey gestures and sounds towards United players at Etihad Stadium.