Republic of Ireland manager Stephen Kenny looks set to be without Enda Stevens for next month's World Cup qualifiers.
The defender may require surgery on a knee injury, according to Sheffield United boss Slavisa Jokanovic.
Stevens has already missed the start of the club season for The Blades.
He was absent for their first Championship game against Birmingham City last weekend.
Stevens also failed to make an appearance in their Carabao Cup clash with Carlisle United.
"Enda will still be a few weeks out," Jokanovic said, looking ahead to Saturday's meeting with Swansea.
"We are thinking too about some surgery and at the moment, we are still waiting for his comeback.".
"We are thinking he can be available with us during the international break or it can be after the international break.
"We are thinking about 4-6 weeks."
Ireland continue their bid to qualify for the 2022 tournament on September 1st, away to Portugal.
It was confirmed earlier this week that no Irish fans will be allowed to attend the game.
Then they have two home fixtures against Azerbaijan (September 4th) and Serbia (September 7th).