Ireland faced club side Ulster in a training session described as 'pretty physical and done in the right manner' by head coach Andy Farrell.
Ulster and Ireland both had games postponed due to fears over the spread of coronavirus across Europe.
A youthful Ulster squad travelled to Dublin to take on an Ireland side which included several provincial team-mates.
"Both sides got a lot out of it and we really appreciate them coming down," Farrell told IRFU TV.
"We're unbelievably grateful that Ulster have come down to the High Performance Centre and had a great outing against the boys,"
"It was a great session and it was pretty physical at times."
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Ireland continue to prepare for the Six Nations match against France and Ulster face games against Dragons, Glasgow and Toulouse in the upcoming weeks.
"The speed of the game was high and it was a notch up from what we are used to," said Ulster full-back Michael Lowry, who was up against team-mates Iain Henderson, John Cooney, Jacob Stockdale, Stuart McCloskey, Rob Herring and Tom O'Toole.
"We've been waiting to get something at this level because we haven't had a game for a couple of weeks.
"Training with Andy and the guys has been a really good experience," added Ulster head coach Dan McFarland.
"We brought a young group down here and being able to train against Ireland has been really helpful for us."