O’Neill regained a place on the pro tour by coming through Q School in 2019. He beat Lukas Kleckers 4-1 in the final round of event one.
He has had several previous spells on the pro tour, and his best run in a ranking event took him to the last 16 of the 2014 China Open, beating Alan McManus, Kyren Wilson and Fergal O’Brien before losing to Mark King.
The former world number 90 has worked as a tiler during spells away from the snooker circuit, though injuries to both of his knees led him to decide to give full time snooker another try.
He won the European Under-19 Championship back in 2003.
In 2020 O’Neill matched his best run in a ranking event by reaching the last 16 of the Scottish Open, notably beating Shaun Murphy before losing to Ding Junhui.