Leinster’s Tommy O’Brien recover's from a back issue and Calvin Nash already ruled out.
Mack Hansen is a doubt for Ireland's opening November international with New Zealand on Saturday.
The wing injured his leg in scoring a try for Connacht in their loss to the Bulls in the URC at the weekend.
Leinster's Tommy O'Brien is currently recovering from a back issue and Munster's Calvin Nash has already been ruled out of the game in Chicago with a shoulder injury.

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