In finding the net against Antonio Conte’s men, the centre-back became the first player to score his maiden English top-flight goal for the Stamford Bridge giants in a fixture against Spurs.
According to Opta, the previous player to do this was Ghana icon Michael Essien, who achieved the feat in 2006.
In that match played on March 11, Essien scored in the 14th minute as Jose Mourinho’s team triumphed 2-1 at Stamford Bridge.
The Accra-born midfielder signed for Chelsea in 2005 after an impressive spell at Ligue 1 side Olympique Marseille but later left for AC Milan after a trophy-laden career that saw him win the Champions League, four FA Cups, and two English top-flight titles.
Along with scoring, the Lion of Teranga captain attempted three shots in the first half for Chelsea, one more than Spurs registered.
Nevertheless, Conte’s side restored parity in the 68th minute through Pierre Hojbjerg after he was set up by Ben Davies.
With 13 minutes left on the clock, Reece James put the hosts ahead after Raheem Sterling profited from shambolic defending by the visiting side.
The experienced centre-back is part of manager Tuchel’s rebuilt defence after the summer departures of Antonio Rudiger and Andreas Christensen.
The 31-year-old played for Napoli since 2014 and made 26 Champions League appearances, making him an ideal fit for a Blues side which will be aiming for a deep run in the competition this season.
Koulibaly signed a four-year contract that will keep him in west London through to the summer of 2026. He will earn an annual salary of around £8.5m ($10m).