Hearts manager Craig Levein has urged more protection for players when they come up against Celtic captain Scott Brown.
Midfielder Harry Cochrane suffered an injury to his collarbone after a challenge from the 32-year-old during the Jambos' 3-1 defeat on Tuesday.
The 16-year-old had to be replaced with Prince Buaben after just 38 minutes of the Scottish Premiership fixture at Parkhead and is likely to miss the next two to three games.
"I think everybody should get a bit more protection from Scott Brown really. But we will see," Levein told BBC Sport.
"I was annoyed about [the challenge]. I watched it back and I think Scott had decided after the game at Tynecastle [when Hearts beat Celtic 4-0], when Harry bossed him, he wasn't going to let that happen.
"I've known Scott for a long time and he is aggressive in the way he plays."
Brown has picked up nine yellow cards this season but was last sent off against Ross County in April, his only red card in three seasons.