Ziyech broke the impasse together with his amazing lengthy-range curler early inside the 2nd half of at Stamford Bridge.
Thiago Silva's header killed off Tottenham, who were furious that Harry Kane had a primary half goal ruled out for a nasty.
Third-positioned Chelsea are now 10 factors behind leaders Manchester City after ending a dangerous run of 4 league games without a victory.
Chelsea had overwhelmed Tottenham 3 instances already this season without conceding a purpose, including knocking their London opponents out of the League Cup semi-finals.
Failing to accomplish that for a fourth time might were a hammer blow to the Blues' bid to reel in City.
Chelsea might not play once more inside the league until mid-February because of the iciness break and their involvement within the FIFA Club World Cup.
But, for the first time on account that December 26th at Aston Villa, Thomas Tuchel's facet tasted league success, giving them a much-wished improve at a time whilst their season turned into in chance of going off the rails.
Tottenham's first defeat in 10 league games seeing that Antonio Conte took charge became a blow to their mission for a pinnacle four end.
They stay in 7th, two points in the back of fourth located Manchester United with two video games in hand.
Tottenham lovers allow themselves down via throwing missiles at Chelsea defender Antonio Rudiger inside the closing levels.
