Arsenal midfielder Aaron Ramsey was forced off in the first half of the Gunners' 1-0 Europa League quarter-final win over Napoli after stretching for a ball in a challenge, and manager Unai Emery says he's unsure if the midfielder will be able to play again this season.
After briefly receiving treatment the Wales international admitted defeat in the 31st minute as he limped from the field.
Henrikh Mkhitaryan took his place in the Arsenal midfield, with the game still scoreless at the time.
With Ramsey already having agreed a pre-contract with Juventus, bringing to an end an 11-year association with the club, a severe injury could mean he has played his last game in an Arsenal shirt.
Arsenal have five Premier League games remaining, as well as a possible three Europa League matches, provided they advance all the way to the final in Baku on May 29.
Emery says he is unsure if Emery has played his last game, but admitted he will need other players to step up in the midfielder's absence.
"It is a muscular injury. Normally it will be some weeks out for him. But we have other players and we can find a performance and rotate players," Emery told BT Sport.
Asked if Ramsey has played his last game for the club, Emery responded: "I don't know."
Despite his guaranteed exit at the end of the season to the Serie A champions, Ramsey has remained an influential figure in Emery’s squad as they continue their quest for a top-four finish and a Europa League title.
He has appeared in 28 Premier League games this season, making 14 starts, and has started six of Arsenal’s last seven contests in all competitions.
Since the start of March, Ramsey has been in fine form, contributing three goals and an assist, including his opener at the Emirates against Napoli in the first leg, which Arsenal won 2-0.
Overall he has scored four goals and added six assists in the Premier League, while adding two goals and an assist in seven Europa League appearances this season.
Moments after Ramsey departed, Alexandre Lacazette broke the deadlock by scoring a 25-yard free-kick, giving Arsenal a 1-0 lead in the match and a 3-0 aggregate lead in the tie.
It also handed the Gunners an away goals advantage, meaning Napoli would require a three-goal victory in the second leg to advance.