[3] He made his professional debut on February 26, 2022, at the OVO Hydro in Glasgow, fighting on the undercard of Josh Taylor vs. Jack Catterall against Damian Esquisabel.

I watched his spars with David Avanesyan and they were 50-50 and it’s testament to Kieran the way he’s able to adapt and fight and mix it under supreme pressure.

Molloy went the distance for the first time in his career, defeating Sandro Jajanidze by unanimous decision in Frankfurt, Germany.

The contest took place at the SSE Arena in Belfast on December 10, 2022, as an undercard fight for Michael Conlan vs. Karim Guerfi.

[20][21][22] On August 4, 2023, Molloy faced former English super-lightweight champion Sam O'maison at Falls Park in Belfast, Northern Ireland.

[26][27] After a hand injury stopped the Ryan vs. Kelly bout, the initial title plans had to be changed, with Conlan eyeing the potential winner between Declan Geraghty and Owen O'Neill for the vacant Irish welterweight championship.

[33] Molloy told Galway Bay FM: "I suppose that I wasn't happy with the structure and the lack of fights, so you have to listen to your gut and go with what is right".

[35][36] Two days later, he was announced as an undercard fight on the 'Coming of Age' boxing card against an unannounced opponent on April 20, 2024, at the Magna Centre in Rotherham.