Born in Ibadan, Nigeria, Adeolokun came to Ireland with his family in 2001. He played a variety of sports as a child, including Gaelic football with Templeogue Synge Street and soccer and did not play rugby union until he attended De La Salle College in Churchtown.
In June 2014, it was announced that Adeolokun had signed for Irish provincial team, Connacht on a one-year deal and made his debut on 6 September 2014.
September 2016 saw him extend his stay at Connacht until 2019.
Niyi was called up to the extended Ireland squad for the November Internationals. He made his international debut against Canada in the November International.
Adeolokun scored 8 tries in 30 PRO12/14 during the 2016/17 & 2017/18 seasons and featured for the Barbarians in their historic win over England in May 2018.
After 82 appearances for Connacht, he signed a contract extensions with the province.
|2018 - present|
|2016 - 2017|
|2014 - 2020|