Republic of Ireland defender Shane Duffy is recovering from an operation to have a blood clot removed from his leg.
The Argus report the 28-year-old will miss this Saturday's Premier League clash at West Ham and is facing the next two to three weeks on the sidelines.
The towering centre-half has been in and out of the side under Graham Potter this campaign but he remains absolutely crucial to his country's hopes of making the Euros.
Ireland face Slovakia in a play-off semi-final on 26 March, with the winners taking on either Northern Ireland or Bosnia in the final.
His injury is a concern, but at this point Duffy's availability for the trip to Bratislava does not look under threat.
Of more concern to Mick McCarthy and the Derry man himself will be his lack of minutes at club level.
He has been an immense presence over the last couple of years, developing a happy knack of plundering crucial goals from set-pieces.
Duffy defied the odds to make October's game against Georgia in Tblisi when a calf problem looked certain to rule him out.
He also overcame an ankle knock in Gibraltar to play in the home fixture against the Georgians last March.