Kenny Dalglish has warned Alfredo Morelos any further suspensions could wreck Rangers' title challenge.
The Celtic and Liverpool legend insists the Colombian's latest stint on the sidelines must be his last this season.
Morelos was sent off during Rangers' win at Parkhead, his second dismissal of the campaign, and will serve the last of a three game ban as Steven Gerrard's team face Hearts on Sunday.
Dalglish believes Rangers haven't quite been the same without their talismanic frontman since returning from the winter break, despite racking up two wins from two.
He told the Sunday Post: "Alfredo Morelos sits out the final game of his three-match ban this afternoon, and the Rangers striker needs to make sure this is his last of the season.
"If he falls foul of referees too often between now and May then he risks having to sit out more games and that will seriously threaten Rangers chances of winning the title.
"That's how vital he is to Steven Gerrard.
"Alfredo needs to get back to the way he was in the early months of the campaign.
"He was well behaved and didn't allow opposition players to overly wind him up.
"But his good behaviour wasn't evident enough a few weeks ago and, rightly or wrongly, he was sent off against Motherwell and Celtic.
"He had to sit out the Scottish Cup win last weekend against Stranraer and the 1-0 midweek victory in the league at home to St Mirren.
"On both occasions it was job done, and that's all that really matters. But you would have expected both games to have been more emphatic.
"The trip to play Hearts is the last Morelos misses, and he will be hoping the team can produce the goods without him because they have struggled a wee bit because of his loss to the team."
