Wolverhampton - Chelsea were made to pay heavily for missed chances as they squandered a lead to lose 2-1 at Wolves on Wednesday.
Ruben Loftus-Cheek looked set to take centre-stage when he marked just his second Premier League start of the season with the opening goal in the 18th minute.
But two goals in four second-half minutes by Raul Jimenez and Diogo Jota brought a dramatic turnaround after the visitors had wasted several opportunities to close out the game.
It was a night to forget for Blues goalkeeper Kepa Arrizabalaga, who committed a howler to concede Wolves' equaliser.
It meant a second defeat in three League outings for Maurizio Sarri's side, which featured five changes in the starting line-up but looked set to claim victory during a comfortable first-half display.
It was a momentous night for Wolves, however, with Nuno Espirito Santo's side recording their first victory in seven league games to bring an end to a slump that had followed an impressive start to the season.
Roberto Firmino came off the bench to score with his first touch as Liverpool came from behind to maintain their unbeaten Premier League start on Wednesday after Jurgen Klopp's decision to ring the changes almost backfired.
Two goals in the space of seven minutes midway through the second-half sealed a hard-fought 3-1 win at struggling Burnley after Jack Cork's 54th-minute effort had given the hosts an unexpected lead against a side they've now beaten just once in the last 12 attempts spanning 44 years.
It means Liverpool remain second, cutting Manchester City's advantage at the summit to two points with a 12th victory of the campaign, and in the process posting the club's best start to a top flight season after 15 games.
They were pushed all the way by a Burnley side now anchored in the relegation zone after an eighth game without victory.