Chelsea secured a win at the City Ground, thanks to a second-half surge sparked by Josh Acheampong's first senior goal.
The Blues were outplayed in the first half but stunned Ange Postecoglou's struggling side with two quick goals after the break. Acheampong's 49th-minute header opened the scoring, before Pedro Neto doubled the lead.
Chelsea ended the match with 10 men after Malo Gusto was sent off late on, while Forest could have scored two or three goals themselves.
Chelsea's win was a significant turnaround after being outplayed in the first half.
Author's summary: Chelsea wins at Forest with a second-half surge.