Frank Lampard was frustrated his Chelsea team were caught on the counter-attack after warning of Wolves' threat, although he acknowledged his side were not good enough at Molineux.
Olivier Giroud's sixth goal in his past four away games in all competitions had the Blues on course for a victory that would have taken them top of the Premier League.
But Daniel Podence netted a fine equaliser and then, with Chelsea chasing a late winner, Pedro Neto ran through at the other end and rifled in a brilliant 95th-minute strike – the latest decisive league goal the Blues have conceded since at least 2006-07.
"We didn't play well enough. It's pretty simple," said Lampard, but he also felt the visitors had the game "under pretty good control" at 1-0.
Therefore the failure to deal with Wolves on the break, a tactic for which they are renowned, was the source of some disappointment.
"We've been given maybe different kinds of games in these last two games," the coach explained. "Particularly where Everton made it difficult for us to break them down, and we didn't really succeed in that.
"Wolves played very much a counter-attacking style late in the game – not just that – but we didn't deal with that.
"The players have to feel that on the pitch, because the message was very clear about the counter-attack and the issue was that they could hurt us. So that's disappointing."
Goal for Wolves. Neto.— Chelsea FC (@ChelseaFC) December 15, 2020
2-1 [90'] #WOLCHE
It was a second straight defeat after the 1-0 reverse at Everton, losing back-to-back league matches for the first time in 12 months and a single day.
Lampard, who is hoping to have Hakim Ziyech and Callum Hudson-Odoi back in training this week, said "there could be some fatigue" and Chelsea "didn't have that zip about us", failing to have a shot on target before Giroud's second-half opener.
But he also recognised Chelsea could not be surprised to lose games if they slip below their usual standards.
With in-form West Ham up next in a London derby, Lampard was asked if this was becoming a "blip".
"That's up to us," he replied. "We had a long unbeaten run, everyone sang our praises. I was the last one to do that.
"It's my job to stay level-headed on both ends, so I shouldn't feel too disappointed tonight, as much as I didn't get too elated after Leeds when we were on the back of a really good run.
"But clearly, when we've performed like we've done today, that's not game management, that's not the quality levels that we are striving for.
"I still think there's a lot of improvement to be done with the group, so I wouldn't say I'm massively surprised.
"My experience of the Premier League tells me that if you drop your standards, which we have in two games, particularly away from home, you can lose football matches. That's a big lesson for the players there."