James Ryan's fitness will be monitored this week to determine if he will be available for Saturday's game against Japan.
The IRFU has confirmed that the Leinster second row has an adductor issue but Ryan is yet to be ruled out of the meeting with Japan at the Aviva Stadium.
If passed fit, the 24-year-old will captain Andy Farrell's side for the games Japan and the USA in July.
Ulster’s Michael Lowry will continue to train with the squad this week despite being left out of the original 37-man squad.
The 22-year-old was brought into camp last week and will continue to train with the squad this week.
The team to face Japan will be named at lunchtime on Thursday.
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