The France under-21 star was thrown into action just three days after joining the Blues from Leicester City- and impressed as Chelsea came from behind to beat West Ham in the Premier League.
The young defender completed a £70 million move from the Foxes in midweek, and with Chelsea looking to instantly return to winning ways, they called on their summer record signing to give them the base they needed in defence.
The Blues struggled to create openings in the first half but defensively they were sound until Michail Antonio bundled home the opener for the Hammers in the second half.
Substitute Ben Chilwell equalised for Chelsea before Kai Havertz turned the game on its head with a winner for Chelsea.
West Ham thought they had the equaliser when Maxwel Cornet finished off brilliantly but VAR intervened controversially to rule out the goal and Chelsea held on for all three points.
The Blues might not have kept a clean sheet, but the balance Fofana’s presence gave them was encouraging and rarely did he put a foot wrong throughout the game.
Another positive from having Fofana was that it allowed Thomas Tuchel to play Reece James as a right wing-back, something they have not been able to do often this season.
Chelsea’s over-all performance though has been fading and the win was the best response to their midweek defeat to Southampton.