France international Djibril Sidibe is a doubt for the World Cup after being diagnosed with a knee injury.
The Monaco full-back suffered the injury during Sunday's defeat away to Paris Saint-Germain, a result that saw Unai Emery's men reclaim the Ligue 1 title.
And coach Leonardo Jardim has confirmed his side were dealt a further blow in a heavy 7-1 thumping due to Sidibe's injury.
"In the most serious cases it is seven weeks; in the less serious, four weeks," Jardim told reporters.
"You have to check that with the specialists. The medical service will make the best decision, I have full confidence.
"Will we be seeing him again this season? I think not."