Frank Lampard says his Chelsea players may be suffering from fatigue after Wolves came from behind to beat the Blues with an added-time winner.
Pedro Neto’s 95th-minute strike gave the hosts a dramatic victory at Molineux and stopped Lampard’s side going top of the Premier League.
Daniel Podence had equalised in the second half after Olivier Giroud put the Blues ahead.
The Portugal forward tiptoed through the Chelsea defence before wrong-footing goalkeeper Edouard Mendy with a shot that deflected in off Reece James.
It came after a fierce Giroud volley from Ben Chilwell’s cross crept through Rui Patricio’s gloves to open the scoring for the visitors.
Neto was denied a late penalty for the hosts after referee Stuart Attwell reviewed his original decision on the pitch-side monitor and judged the Wolves forward was not fouled by James.
But the 20-year-old broke away in the 95th minute and fired a low strike into the far corner beyond Mendy to earn Wolves only their second win in six games.
It is a second successive defeat for Chelsea after they were beaten at Everton on Saturday, another game in which they could have gone top of the table.
“There could be some fatigue,” said Lampard, whose side have already played five games in December.
“I hate to say it after a defeat because it feels like an excuse but even in the first 60 minutes when we were the better team, we didn’t have a zip about us.
“We’ve travelled up to Everton, came back and then travelled to Wolves but everyone is in the same boat.
“We have a couple of injuries in areas which means I can’t make too many changes so I understand that side of it.”
Wolves had failed to score in their previous two games after losing talismanic striker Raul Jimenez, who suffered a fractured skull against Arsenal.
The Mexican played in every Premier League match for Nuno Espirito Santo’s side last season, scoring 17 goals.
Against Chelsea the manager turned to 18-year-old club-record signing Fabio Silva in his search for goals.
Silva, who joined for £35m from Porto, did have the ball in the net but only after straying offside and generally found it a tough evening up against an experienced defender twice his age in Chelsea’s Thiago Silva.
Portuguese duo Podence and Neto produced the main goal threat for the hosts, who also sold Diogo Jota to Liverpool in the summer, and looked capable of shouldering the attacking burden in Jimenez’s absence.
Wolves also looked solid at the back, with Nuno reverting to three central defenders after playing with a back four in their past four games.
The results lifts his side to 10th in the table.