McCarthy first began playing rugby for Old Belvedere, and went on to play for St Michael's College in the Leinster Schools Senior Cup.
Nick represented Leinster at under-16 and under-18 level, and joined the provinces sub-academy in 2013, before entering the full academy ahead of the 2014/15 season.
McCarthy represented Ireland at under-18 level in 2013, and Ireland under-20s in 2014, winning 18 caps and captaining the side in 2015.
He got promoted to the senior squad ahead of the 2017/18 season, and featured for the team in the semi-final and final during their 2017/18 Pro14 season.
He joined Munster on a two-year contract after the completion of the 2018/19 season, and made his debut for the province in their opening 2019/20 Pro14 game against Welsh side Dragons in 2019.
McCarthy made 8 appearances for Munster by June 2020.
In April 2021, it was announced that McCarthy would be leaving Munster and rejoining Leinster.
Career
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Chicago Hounds Scrum Half |
2023 - present |
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Ireland U20's Scrum Half |
2014 - 2015 |
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UCD RFC Scrum Half |
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St Michael's College Scrum Half |
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Leinster Rugby Scrum Half |
2015 - 2023 |
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Munster Rugby Scrum Half |
2019 - 2024 |
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USA Scrum Half |
2023 - 2024 |
