Debuchy managed just 15 minutes on his comeback game before being forced off with a hamstring problem, and Gunners boss Arsene Wenger has serious concerns over his fitness.
The France international last started for Arsenal 370 days ago and was a surprise name on Wenger's teamsheet with Carl Jenkinson having filled in for the injured Bellerin of late.
Debuchy, who spent the second half of last season on loan at Bordeaux having attracted the attention of Manchester United, has told Wenger he thinks it could be a serious injury.
"Debuchy, he thinks it's a severe one," he said. "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 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."