Shane Duffy is recovering from a minor operation to have a blood clot removed from his leg, according to local media reports in Brighton.
The Ireland international has been in and out of the team under Albion manager Graham Potter but remains central to the Republic's Euro 2020 qualification hopes.
The Argus reports that the defender will be missing for "not too long", easing any potential fears for his participation in Ireland's play-offs at the end of March.
Duffy has scored three goals in 33 Ireland caps, including a late equaliser away to Denmark last July.
At club level, after three seasons as a first-team regular, he has found himself behind Lewis Dunk, Adam Webster, and Dan Burn in the pecking order, although the latter suffered a broken collarbone against Chelsea on New Year's Day.