McCloskey is a major doubt while Beirne faces a disciplinary hearing this week.
Ireland head coach Andy Farrell will be sweating over both injuries and possible suspensions ahead of Saturday’s clash with Japan at the Aviva Stadium.
Stuart McCloskey is a major doubt after damaging his groin in the defeat to New Zealand at Soldier Field.
Second-row Eadestown Tadhg Beirne faces a disciplinary hearing this week following his red card against the All Blacks.
Ireland are expected to contest the decision to upgrade Beirne’s yellow card for a high tackle on Beauden Barrett - who has offered to support Beirne’s case.

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