Chelsea head into Wednesday's meeting with Zenit knowing they must match Juventus' result against Malmo to seal top spot in Champions League Group H.
The Blues are in a tricky patch of form and have plenty of injury issues to contend with, so this game is by no means as simple as it perhaps should be for Thomas Tuchel.
Here's how the boss could set up.
Chelsea predicted lineup vs Zenit
1. Goalkeeper & defenders
Edouard Mendy (GK) - Has looked a bit shaky in recent weeks but is still Chelsea's number one without a shadow of a doubt.
Cesar Azpilicueta (CB) - Benched for the West Ham game, Chelsea's skipper may need to bring his experience for this one.
Andreas Christensen (CB) - Thiago Silva doesn't deserve to be benched at all, but his legs will need resting and this may be the best chance Tuchel will get to do that for a while.
Antonio Rudiger (CB) - A constant force on the left. With Trevoh Chalobah still injured, this is a no-brainer.
Reece James (RM) - One of the best players in England last month, Chelsea need James to rediscover that form soon.
Ruben Loftus-Cheek (CM) - RLC has struggled in recent weeks, but with Jorginho, N'Golo Kante and Mateo Kovacic all out, he'll get another chance to prove himself.
Saul Niguez (CM) - Speaking of another chance, Saul is slowly running out of time to convince Chelsea fans that he is worth keeping around. If he fails here, it could be game over. Depending on Tuchel's level of faith, this could easily be Mason Mount's spot.
Marcos Alonso (LM) - Alonso picked up a back problem against West Ham but is thought to have recovered. With Ben Chilwell out too, that's big.
Callum Hudson-Odoi (RW) - One of Chelsea's best players recently, but has surprisingly been benched for the last two games. Definitely needs to return.
Kai Havertz (ST) - Havertz has been training after picking up an injury against West Ham and should lead the line here, particularly with Romelu Lukaku not yet fit enough to start.
Timo Werner (LW) - Werner is close to full fitness and should get the chance to rekindle his impressive partnership with Alonso from the early weeks of the season.
You can read 90min's preview of Zenit vs Chelsea here.