Martin O'Neill has urged Nicky Shorey to show the character to force his way back into the Aston Villa team.
The summer signing from Reading has not started a Premier League game for two months, having been first choice at left-back in the early weeks of the season.
Luke Young has been preferred at left-back of late and the situation has led to speculation that Shorey could leave Villa during the January transfer window.
However, O'Neill is not planning to offload the England international and has called on Shorey to emulate the example set by Stiliyan Petrov.
"Players want to play every week and it's been a difficult start for him," said O'Neill. "But while I'll monitor every single situation, I'd prefer to strengthen the squad rather than let people go.
"People can come to a football club and they can have a few downturns, but you have to try to fight back.
"Stiliyan Petrov would be the best case in point here. He has been as consistent as anyone for us this season and he is vindicating the faith I had in him.
"I don't just bring people to the football club for the sake of it. You have to battle to get into the side.
"Look at Luke Young. He came here and it took a while for him to get into the swing of things, but he's battled back and now he's playing at left-back as if he'd done it all his life and he's done brilliantly for us."