Career
He can play either Number 8 or Flanker and is the first Waterford player to play for since Ben Cronin in the early 1990s. O'Donoghue made his debut for on 19 September 2014, coming on as a replacement against Zebre in the Guinness Pro 12. He signed a three-year contract with in January 2015.
He scored a try in the 25-25 draw with Scarlets on 21 February 2015. O'Donoghue came off the bench during the 2015 Pro12 Grand Final on 30 May 2015. O'Donoghue started at Openside Flanker for against Treviso on 5 September 2015.
O'Donoghue captained Under-20 in their opening game of the 2014 IRB Junior World Championship against France Under-20 on 2 June 2014. On 7 March 2016, O'Donoghue was added to 's squad for the final two rounds of the 2016 Six Nations Championship, his first senior international call-up.