Arsenal manager Arsene Wenger feared Mathieu Debuchy would suffer an injury against Bournemouth, due to his history of setbacks.
The right-back, who appeared set to leave in the summer, was handed a surprise start against the Cherries, with Hector Bellerin out injured.
However, Debuchy appeared to injure his hamstring in Arsenal’s 3-1 win and was replaced by Gabriel, leading Wenger to admit that he was worried about the former Newcastle United defender sustaining such an issue.
"Debuchy, he thinks it's a severe one," he told reporters.
"Don't go too far because I have to speak to medical people, but you can only assess it really after 48 hours. You have to let it bleed and after, usually they have an MRI scan 48 hours later to see how big the damage is.
"When I picked the squad I imagined that something could happen to Debuchy because he's had many setbacks."
Debuchy has made just 23 appearances for the club since leaving Newcastle in 2014.
Arsenal are currently fourth in the Premier League, three points behind leaders Chelsea, and are next in action in the EFL Cup against Southampton on Wednesday.