A stoppage time equaliser from Zenit St Petersburg meant holders Chelsea failed to top their Champions League group.
The entertaining clash ended 3-3 at the Krestovsky Stadium in Russia.
Thomas Tuchel made eight changes to his team, citing a busy December fixture list for the need for fresh legs.
Timo Werner got the visitors off to an excellent start when he instinctively finished inside the box after just 2 minutes.
Zenit bounced back before half-time with two goals in quick succession through Claudinho and Sardar Azmoun.
Romelu Lukaku made his first start since September, and although lacking sharpness, scored the equalising goal from a close range thanks to Timo Werner's cut-back after 62 minutes.
Werner then scored an excellent solo goal, freeing himself with agile movement inside the box before finishing past Mikhail Kerzhakov with five minutes remaining.
But Zenit would have the last say as substitute Magomed Ozdoev unleashed a stunning half-volley four minutes into injury-time.
The result means Chelsea finish second behind Juventus in Group H.
Speaking after the game, Tuchel was angry with his players for relaxing after going ahead in matches.
"I won't take it personally that you make a judgement here that my players are not listening to me, which I don't find so nice but I leave it with you and your opinion," said Tuchel.
"I think that we had a very good first 15 minutes and we stopped doing the things we did in the first 15 minutes.
"We were forgetting why we were the better team, because of the investment, the level of concentration, the level of physical investment was high enough to be the better team.
"Once this drops, five, 10 per cent, and it does; once we start managing results and changing our behaviour from what the score is, we get punished at the moment.
"It happened to us at West Ham and it happened again today. The reaction was good again, that shows me that it's not about what we can do, because we can do it.
"Suddenly when we concede two goals we can step up, we can show a reaction. But once we have the lead we give it away again, like also today.
"The last six minutes again we started playing balls back, we started not attacking in the same aggression, the same hunger as before and we got immediately punished, now twice."
