David Turnbull made his first appearance of the season following knee surgery as Motherwell lost 2-1 to St Mirren in the Premiership.
The midfielder, who saw a move to Celtic collapse last summer after the injury was detected, came on in the 71st minute.
Motherwell manager Stephen Robinson said the club would be cautious with the 20-year-old as they reintroduced him to the team.
He said: “It was good to see David back. That’s probably the limit of where he is in terms of game time.
“We’ve got a free week now where we can get him fitter. But David is not ready to start football matches.
“Believe me, if he was ready, he’d be starting, because I could think of no one better to start for us.
“The long-term future of David Turnbull and Motherwell is more important than a short-term fix.”