Pearce came off the ground in agony in the 25th minute after he stuck out his left arm in an attempt to tackle Dragons back-rower Tariq Sims.
With his arm fully stretched out, Pearce’s yell in pain could be heard on Nine’s NRL broadcast instantly after he connected with the on-rushing Sims.
The 31-year-old appeared to be in excruciating pain immediately after the incident as the club doctors attended to him.
“He’s in distress, there are tears in his eyes,” league legend Andrew Johns said on Nine’s coverage.
“He knows he’s torn his pec, he’s devastated.”
Nine’s rugby league reporter Danika Mason confirmed shortly after the incident that the Knights were bracing for news of a pectoral tear when Pearce undergoes scans next week.
“It is a suspected torn pec,” Mason said.
“He was in a lot of pain when he entered the sheds. We hear he is quite upset.”
If it is a confirmed pectoral tear for Pearce, it would not be the first time he has suffered the injury, having undergone a similar ordeal three years ago which resulted in a three-month recovery process.