Kilmarnock midfielder Gary Harkins is facing six weeks on the sidelines after breaking his ankle.
The 26-year-old sustained the injury after being tackled in training by team-mate Zdenek Kroca.
Harkins has scored three times in 20 appearances for Killie since joining last summer.
As well as Monday's visit of St Mirren, Harkins will miss the Scottish Cup clash against his former club Dundee at Dens Park on Saturday.
He began his career at Blackburn Rovers, and, after spending time on loan at Huddersfield Town, Bury and Blackpool, moved to Grimsby Town in 2006.
A return to his native Scotland was next for Harkins as he signed for Partick Thistle in 2007, joining Dundee two years later and then clinching a move to Scottish Premier League Killie.