McKeon went to secondary school in Coláiste Iognáid in the city, and was later a student in NUI Galway, the local university.
McKeon made his European debut on 10 December 2012, coming on from the bench against Gloucester and played a part in three of his side's six games in the 2011–12 Heineken Cup, the team's first ever appearance in the competition.
[7] At European level, McKeon played in four of Connacht's 2012–13 Heineken Cup matches, and started in three of these games.
McKeon made three appearances in 2013–14 Heineken Cup, coming off the bench in a memorable win over Toulouse and starting two more games.
[9] McKeon made his 50th senior appearance for the side on 26 September 2014 against Glasgow Warriors as Connacht's winning start was brought to an end.