North Melbourne onballer Luke Davies-Uniacke has been subbed out of Sunday's clash with West Coast at Marvel Stadium.
Initial fears suspected Davies-Uniacke sustained a shoulder injury after being tackled by Eagles forward Willie Rioli in the second quarter of the match, however the Roos midfielder also appeared groggy as he was assisted off the field.
The tackle forced Davies-Uniacke into the ground, with a cut appearing near his right temple as he gained further assessment from medical staff.
While a shoulder issue may be present, the Kangaroos confirmed a head knock was the reason for the change.
Medical substitute Aiden Bonar was brought into the match in place of Davies-Uniacke, with the Roos carrying a six-point lead into the second term.
Davies-Uniacke recorded just the four disposals and one tackle prior to being subbed out of the match.
Fellow Roos onballer Tarryn Thomas was also ruled out of the second half after suffering a rib injury after an attempted smother in the final minutes prior to the half-time siren.
Eagles top-up player Brayden Ainsworth joined the North Melbourne pair in having his day curtailed, being replaced by West Coast medical sub Luke Edwards.
Ainsworth suffered an ankle injury after recording six possessions and two tackles in the game. He was named in Adam Simpson's side as a top-up player after being delisted at the end of last year following four seasons with the Eagles.
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