On 23 March 2013 Duut fought Dustin Jacoby at Glory 5: London, winning by TKO in the first round.

[10] Duut was part of the Light Heavyweight Tournament Glory 9: New York - 2013 95kg Slam on 22 June 2013, losing in the first match to Tyrone Spong.

[12] Duut lost his third fight in a row on 8 March 2014 at Glory 14: Zagreb by KO in round 1 to Igor Jurković.

[13][14] He broke the losing streak during the North vs. the Rest event, when he won a unanimous decision over Andre Schmeling.

[20] Despite losing his next fight to Mourad Bouzidi as well, he was granted a berth in the Glory Light Heavyweight Contender tournament.