The 22-year-old came into the Munster fold from Garryowen after a phone call from Anthony Foley in November.
And after sitting on the bench in Munster's narrow win over Ulster back in November, Cronin eventually got his first taste of action when he replaced Duncan Williams in a 28-13 win over Leinster.
"I didn't come on against Ulster, but then against Leinster at Thomond Park on St Stephen's Day, when I was told to warm up, my reaction was like 'are you sure?' It is great, you are dying to get into the action," Cronin told the Limerick Leader.
"Your first appearance is always going to be nerve-racking. I came on for a line out. I remember looking at it coming down and you are looking at these monsters of men.
"You are wondering is it all real. But once the game goes again, a fella runs into you, it is nothing different.
"Andy Lee came into our dressing room afterwards and they got me into the middle of the circle of players with him. That was surreal. Everyone came in, all the international boys who were rested for that day.
"It was a time when you really feel part of the squad. You feel these guys look at me as a player, not just filling numbers. That is something you will have in your memory banks forever."
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