[2] On 20 February 2016 Sheehan faced Tristan Caetano at Siam Warriors for the ISKA Muay Thai European Bantamweight title.
[3][4] On 15 June 2016 Sheehan travelled to Japan to face the reigning ISKA Muay Thai World Bantamweight champion Shiro at the Shin Nihon Kickboxing Association "WINNERS 2016 2nd" event.
[6] Sheehan was scheduled to defend his ISKA Muay Thai European title against Steve Irvine at Power of Scotland 24 on 29 April 2017.
[16] On October 19, 2019 Sheehan was scheduled to face Andrei Mezentsev for the ISKA Muay Thai World Flyweight title at a Siam Warriors event.
On March 8, 2020 Sheehan faced Klairung Sasiprapa at Capital 1 for the WBC Muay Thai International Super Bantamweight title.