Aaron Ramsey may have played his last game for Arsenal after suffering a muscular injury during their Europa League quarter-final against Napoli.
The midfielder pulled up feeling the back of his thigh in the 33rd minute and was replaced by Henrikh Mkhitaryan.
Ramsey, 28, will join Juventus as a free agent this summer, ending his 11-year spell with Arsenal.
"It is a muscular injury. Normally it will be some weeks out for him," said Gunners boss Unai Emery.
The typical recovery time for a minor hamstring injury is four to six weeks.
Arsenal have five Premier League games remaining.