Arsenal striker Gabriel Jesus is set to undergo an MRI scan on a groin injury amid fears the Brazil striker could be set for a spell on the sidelines.
Jesus missed Saturday's 2-0 win at Aston Villa and will be assessed in the coming days with Arsenal next in action against Brighton on Saturday.
"Unfortunately on Thursday in the training session, just at the end he felt something in his groin," Arsenal boss Mikel Arteta told a news conference.
"We'll need to assess him. We need to have an MRI scan to see, but he wasn't available for the game. We have to see [if it is a long-term injury].
"Probably tomorrow or Monday we'll have the results to see if it's a matter of days or weeks. We don't know."
The outcome of Jesus' scan could yet have an impact on whether Eddie Nketiah is allowed to join Nottingham Forest this month.
Sources have told ESPN that the Gunners are on the brink of finalising a deal with Forest worth around £30 million ($39m) plus bonuses but when asked whether Jesus' injury could impact Nketiah's future, Arteta said: "At the moment, Eddie is our player. He's very committed to us. Regardless of the noise, he's here and he wants to be here with us. He's really happy that we won the game."
Arsenal won a hard-fought game at Villa Park thanks to second-half goals from Leandro Trossard and Thomas Partey, both coming after a stunning stop from David Raya to deny Ollie Watkins.
"When we had to rely on certain individuals we did, like the situation of David that is an unbelievable save," Arteta said.
"When we made the changes, the impact they had was tremendous. When the team starts to be equipped that way and starts to be able to navigate through different contexts in the match, it becomes a team that can win in every place. Today we showed that."