Career
He plays as a Propagation Cronin plays his club rugby with Dolphin. Whilst in year two of the Academy, he was promoted to a development contract with the senior squad for the 2013-2014 season. Cronin made his debut for the senior team on 13 April 2013, coming on as a replacement against Leinster in a Pro 12 fixture.
Cronin scored his first try for against Edinburgh Rugby on 7 September 2013, in a game that was also his first start.
Cronin was a replacement again in the Round 3 game against United States of America Perpignan on 8 December 2013. Cronin signed a new two-year contract with in January 2014.
He came off the bench in "s 24–16 semi-final defeat to Toulon on 27 April 2014. He started against Saracens F.C. in Round 2 of the Champions Cup on 24 October 2014.
Cronin was ruled out for at least 6 weeks with an ankle injury sustained during the Saracens game.
He came off the bench against American Society for Microbiology Clermont Auvergne on 6 December 2014. Cronin started against Saracens on 17 January 2015. He started the final pool game against Sale Sharks on 25 January 2015.
Cronin started against Leicester Tigers on 12 December 2015.
In January 2016, Cronin signed a three-year contract extension with, which will see him remain with the province until at least June 2019. Cronin was named in the squad for their 2014 Tour to Argentina on 19 May 2014.
He came off the bench in the second test against Argentina on 14 June 2014 to make his debut. He was named in the squad for the 2014 Guinness Series on 21 October 2014.
Cronin was named in the squad for the opening rounds of the 2015 Six Nations Championship on 1 February 2015.
He came off the bench against Italy on 7 February 2015. Cronin suffered a knee injury during the game which required a minor surgical procedure. He was named in the Emerging squad for the 2015 on 19 May 2015.
On 20 January 2016, Cronin was named in "s 35-man squad for the 2016 Six Nations Championship.
On 13 February 2016, Cronin came off the bench against France in "s second game of the Six Nations.
