Sullivan attended St. Andrews College in Booterstown, Dublin and plays his club rugby with Lansdowne RFC.
After impressing at U19 level, Sullivan was included in the Ireland U20 squad for the 2018 Six Nations.
In 2019 he joined the Connacht Academy l having impressed in the Energia All-Ireland League. The winger also stood out for the Connacht Eagles in the 2019/20 Celtic Cup campaign.
In June 2020 he was named in the Connacht senior squad.
(LS June 24, 2020)
|2019 - present|
|2020 - present|
|2018 - 2019|