Doris is still on course for World Cup
There was concern that Ireland U20 captain Caelan Doris had succumbed to another injury that might threaten his World Cup involvement in France.
The Leinster back-row forward has already had to forfeit the Six Nations this season due to a serious hamstring injury.
Officially announced as the Ireland captain on Monday morning, Doris was quickly removed from a preparatory match against Japan on Tuesday with an injury at Wanderers RFC.
It was merely a precautionary decision by coach Noel McNamara, who was careful to withdraw any player with the slightest setback.
It came amid doubts over the availability of Munster's impressive Jack O'Sullivan.
Ireland have already lost centre Angus Curtis, hooker Ronan Kelleher, flanker Sean Masterson, hooker Eoghan Clarke and wing Peter Sullivan to injury.
It is expected Doris will recover in time for Ireland's opening match against hosts France at Stade Aime Giral next Wednesday in what is certain to be a hostile environment.
IRELAND U-20s WORLD CUP FIXTURES
Wed May 30: France v Ireland, Perpignan, (KO8.0 Irish time, live eir Sport 2).
Sun June 3: South Africa v Ireland, Narbonne, (3.30 Irish time, live eir Sport 2)
Thurs, June 7: Ireland v Georgia, Narbonne, (5.30 Irish time, live eir Sport 2).
Semi-finals: Tues, June 12.
Final: Sun, June 17.