Brisbane have been forced to bring on their medical substitute after young star Zac Bailey was ruled out of Sunday's clash with Richmond due to a suspected sternum injury.

Bailey suffered the ailment in the second quarter of the match at the MCG, requiring medical assistance on the sidelines after the a collision with Richmond's Marlion Pickett in the middle of the field.

He ventured down to the rooms shortly after gaining attention from medicos on the sidelines.

"He was saying to the doc he was coughing something up and kept pointing to his sternum," Channel 7's Jimmy Bartel told the broadcast of Bailey's injury.

"He's copped a pretty heavy knock."

According to 3AW, Bailey will require scans in hospial, while Brisbane have noted the ailment to be a chest issue.

Brisbane were quick to bring medical sub Darcy Fort into the game, with Bailey's evening ending early after recording nine possessions and four marks.

Meanwhile, Richmond veteran Dylan Grimes was also subbed out of the match, having suffered a hamstring injury early into the second half.

Grimes hobbled off the field and down into his side's rooms before the club concluded his day was cut short due to injury.

The Tigers brought small forward Maurice Rioli into the game in a matter of minutes.

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