A goal for each team to celebrate provided plenty of talking points in the first half, which was packed with end-to-end play.
Watford took control of the game right away, dominating ball possession and pressing for an early goal.
The match was called off in the 13th minute after the medical team had to rush to help a fan who had collapsed. It was re-started shortly after.
Chelsea took the lead in the 29th minute when Mason Mount scored a nice goal assisted by Kai Havertz, giving them a 1-0 lead as the game progressed.
More from the hosts, who stayed focused on regaining control of the game as they began to cause more problems going forward.
Emmanuel Dennis equalized in the 43rd minute of the game, bringing the score to 1-1The visitors were ripped apart by the forward after a blunder.
Chelsea started the second half by taking Saul Niguez off and replacing him with Thiago Silva, who was already on a yellow card.
Watford gained confidence as the game progressed, since they exerted so much pressure on the visitors while dominating possession of the ball.
In the 73rd minute, Hakim Ziyech gave the Blues a 1-2 lead as Mason Mount assisted him before he completed for the advantage.
More chances were generated as the game progressed, and the game ended with Watford 1-2 Chelsea, keeping the Blues atop the league.
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