Motherwell midfielder Stephen Pearson has been ruled out for six weeks after suffering several broken ribs and a punctured lung.
He was taken off injured during Friday's 2-1 win over Dundee United and remains in a Glasgow hospital.
Pearson, 33, told Motherwell's website: "I'm gutted to miss our upcoming games, but there's very little I can do for this other than rest up.
"I'll hopefully be back as soon as possible to help the lads."
The former Scotland international had to be substituted after 34 minutes of a game in which skipper Keith Lasley and Josh Law were also forced off through injury.