Manchester United boss Ole Gunnar Solskjaer has some big choices to make ahead of their trip to the Nou Camp on Tuesday.
The Red Devils are facing a massive task as they look to overcome a 1-0 deficit and pull off another dramatic Champions League comeback.
Solskjaer had one eye on their Barcelona showdown as they edged a 2-1 win over West Ham on Saturday - and the Norwegian confirmed one player who will start in Spain.
Midfielder Scott McTominay has enjoyed a strong run of form recently, and Solskjaer confirmed he was left out against the Hammers in order to keep him fresh to start again in midweek.
Ole Gunnar Solskjaer criticises UEFA over Barcelona matches in Champions League
Speaking about McTominay, Solskajer said: "He’s a young boy and that mental and physical output on Wednesday was a lot and he’ll be needed on Tuesday.
"He needed a break today."
Marcus Rashford was also left out of the starting line-up against the Hammers but came on to make an impact.
"Rashy has been injured and ill and it was about him working hard (against Barcelona)." Solskjaer revealed.
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The Norwegian also expressed his frustrations with Uefa given their fixture pile-up after admitting they were fortunate to emerge with a win over the Hammers.
"We have a game on Tuesday night too which may have played on the player's minds," he said.
"But I'm not sure why we played last Wednesday and then we play next Tuesday. That is my little complaint to UEFA.
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"Playing on Wednesday, and today and again on Tuesday played a major factor. It’s a juggling act but I and we got away with it today.
"We rested a couple, thankfully, we got through it and we will be ready for Tuesday.
"With a performance like this we all know we will struggle in Barcelona, and we will have to improve."
