Motherwell boss Graham Alexander is hopeful skipper Declan Gallagher will be back soon from injury.
Gallagher dropped out of the team which secured Motherwell's second consecutive win.
Steven Lawless was also missing from the squad as Well beat Dundee United 2-1 to move six points off the bottom of the Scottish Premiership.
Alexander, whose team travel to Celtic Park on Saturday, said: "Steven Lawless felt his knee in training. He has had a scan and it's not going to be too long, a couple of weeks.
"Dec has had a scan on a muscle injury and we are waiting on the results. Touch wood, it doesn't seem too serious so we are hoping that will be pretty soon as well.
"We are going to get this. I think Covid has been extremely hard for all football clubs to keep players' levels of fitness up and these injuries come along.
"Hopefully it doesn't hurt us too much but Ricki (Lamie) stepped in and we won the game so fair play to the players who have been waiting for their opportunity."