Aaron Ramsey will play no further games for Arsenal before joining Juventus in the summer after Unai Emery confirmed his hamstring injury will rule him out of the Gunners' season run-in.
The midfielder, who will sign for Serie A champions Juve on a free transfer at the end of June, suffered the problem during the Europa League quarter-final triumph over Napoli.
There were hopes that Ramsey would be able to recover in time to play a part before the season ends, with Emery's side potentially still having a maximum of five matches left, should they advance to the Europa League final.
But the Spaniard has now revealed that there is no hope of Ramsey returning in time.
He told reporters: "He was in a good moment when he was injured.
"I said to him, 'I want to do something important in your last matches here' - though he could come back maybe in the future.
"I want to do something important. It will not be with him on the pitch - but still with him, with us."
Ramsey made a total of 350 appearances during his time as an Arsenal player and is the longest-serving current member of the first-team squad, having signed for then-manager Arsene Wenger from Cardiff City in 2008.
Without the 28-year-old, Arsenal face Valencia in Thursday's Europa League semi-final looking to end a run of three defeats in a row.
A shock home defeat to Crystal Palace was followed up by a 3-1 loss at Wolves before Emery's side were again beaten on the road, this time by Brendan Rodgers's Leicester City.
Those results have left their hopes of securing a top-four finish, and a place in next season's Champions League, particularly vulnerable as the Gunners now need those in front of them to drop points.
Despite a home defeat to West Ham, Tottenham remain four points ahead of their north London rivals in third, while Chelsea, who are currently fourth, are two points better off than Emery's men.
That makes the Gunners' progress in the Europa League all the more vital, with Europe's secondary competition offering the winners a place in the Champions League.
Should they advance past Valencia, Arsenal will face either Eintracht Frankfurt or Chelsea in the final, which takes place on May 29.