Arsenal manager Unai Emery has revealed that right-back Hector Bellerin is still a while away from being able to start a game - despite making his return from a serious knee injury.
The Spaniard was a late substitute in Tuesday's 5-0 win over Nottingham Forest, but managed to grab an assist moments after coming on, leaving many fans believing that Bellerin looked ready to return to the starting lineup.
He said: "He wanted to play 90 [minutes]. He said I'm ready and wanted to play. I think no [he won't be ready to start against Manchester United]. Maybe in his mind yes. We need to listen to the doctor.
"The first minutes were amazing for him. The most important for him is his attitude. He wants to help us."
However, the manager was much more convincing when asked about Rob Holding, who played the entire game and marked his return from a serious knee injury with a powerful header to put Arsenal 2-0 up.
"It is perfect to have more options at centre back. His spirit, his positive minutes. Every day in training he helps us to have more performances like a team," Emery added.
"He needed to take minutes and confidence. It was a perfect match. He was a little tired at the end, he's happy."
Kieran Tierney also made his debut after recovering from a groin injury, in what was a perfect match for Arsenal, They welcomed back three defenders and stormed to a 5-0 win thanks to goals from Gabriel Martinelli, Holding, Joe Willock and Reiss Nelson.
They will look to carry that momentum over to the Premier League when they meet United on Monday, as they look to establish themselves as a permanent part of the top four.