Ole Gunnar Solskjaer hopes Marcus Rashford and Nemanja Matic will be able to feature in Manchester United's Champions League quarter-final clash against Barcelona .
Rashford sat out last week's trip to Wolves with an ankle injury and started Tuesday's training session doing individual work, before joining the rest of the group in a session that Matic missed.
The Serbian midfielder was not spotted when the 20-man squad arrived at the Lowry Hotel on Tuesday night, while the injured Ander Herrera was also missing.
However, youngster James Garner was among the players who checked in ahead of the game.
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Eric Bailly, Alexis Sanchez and Antonio Valencia all miss out.
Solskjaer said: "We still hope maybe that Nemanja can be ready. Ander (Herrera is) probably out, but Eric (Bailly) and Antonio (Valencia) are definitely out, yeah.
"Marcus needed an extra warm up and hopefully, he won't get a reaction.
"He joined parts of it at the end but he couldn't join the boxes, which is the fun part of training, so let's see tomorrow. Hopefully, he'll be ready."
The Norwegian says the comeback against PSG has given the side belief but there are few tougher asks than shackling Lionel Messi.
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"Well, what kind of plan can you have to stop one of the best players in the world?" Solskjaer said.
"As Chris (Smalling) says, we're looking forward to it, relishing the opportunity but this season we've played against Juventus and (Cristiano) Ronaldo, PSG with (Kylian) Mbappe.
"We've had Chelsea and (Eden) Hazard. Neymar didn't play against us.
"I think the better an opponent... (Luis) Suarez as well, (Philippe) Coutinho and Messi will keep our defenders on their toes, so let's see how we manage tomorrow."
Provisional squad: De Gea, Romero, Grant, Dalot, Darmian, Jones, Lindelof, Smalling, Rojo, Shaw, Young, Garner, Fred, Matic, Gomes, Lingard, Mata, McTominay, Pereira, Pogba, Lukaku, Martial, Rashford.
