Alan Dillon (37) was elected to the 33rd Dáil on his first electoral run, replacing former taoiseach Enda Kenny in Castlebar.
A former Mayo GAA footballer, Dillon is a two-time All-Star winner and was a high-profile player with over 100 games for his county's senior team.
Kenny tipped him as someone who could rise through the ranks of Fine Gael and potentially hold a ministerial position.
Dillon retired from inter-county football in 2017, going on to co-found Dillon Engineering Services, which works with the pharma and medical devices sectors.
He has an MSc in Pharmaceutical Science from the Royal College of Surgeons and a BSc in Applied Mathematics and Biology.
He is also a STEM ambassador for Science Foundation Ireland and a part-time lecturer with the University of Limerick.
A new father, Dillon lives in Castlebar with his wife Ashling.