[3][5][6][7] In 2014, Dalby gained two victories in the Cage Warriors, including a TKO stoppage of Sergei Churilov to earn the CWFC Welterweight Championship.

[8][9] Dalby made his promotional debut against Elizeu Zaleski dos Santos on 30 May 2015 at UFC Fight Night 67.

[14] Dalby was expected to face Bartosz Fabinski on 10 April 2016 at UFC Fight Night 86.

[15] However, on March 2, Fabiński was removed from the card due to undisclosed reasons and replaced by Zak Cummings.

[19] Despite struggling with depression and alcoholism stemming from unsuccessful UFC stint, Dalby racked up 3–1 (1 NC) record in Cage Warriors including winning interim Welterweight Championship.

[23] Dalby was scheduled to face Danny Roberts on 21 March 2020 at UFC Fight Night: Woodley vs.

[28] The fight result turned to no contest after Ronson received USADA handed 22 month suspension for testing positive for Metandienone.

[46] Dalby was scheduled to face Elizeu Zaleski dos Santos in a rematch on November 9, 2024 at UFC Fight Night 247.

[47] However, Dalby withdrew from the fight for unknown reasons and was replaced by promotional newcomer Zach Scroggin.