Arsenal could welcome back captain Pierre-Emerick Aubameyang for the trip to Wolverhampton Wanderers on Tuesday, but three other key men are still a doubt.
Mikel Arteta revealed after the game against Ole Gunnar Solskjaer's side that Aubameyang was in quarantine after making the trip but the club were working with the government and the Premier League about bringing him back sooner.
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"There's still some things to clear up. Maybe yes, maybe no," Arteta said before the game at Molineux.
We don't know. We're still doing some paperwork at the moment
Kieran Tierney has missed Arsenal's last three games with a muscular issue, while Bukayo Saka missed the game against United with a sore hip and Arteta has confirmed that they are still out of training.
"We don't know yet [if they'll return]. Today we've got a training session and they haven't been able to train with us yet, so I think it will be really difficult for them.
"But I don't know, we're going to try to last-minute see how they are feeling."
Lacazette, who has been in fine form in front of goal since mid-December, fell heavily late during the game against United, but Arteta is expecting him to pass concussion protocols and be fit to face Nuno Espirito Santo's side.
"We have to follow the protocols, that we have to test him and make an x-ray," he explained.
He was completely fine after the game, he was fine yesterday and he has slept well. I'm expecting him to be available.