Amateur

Previously a junior pool champion, O'Connor qualified for the snooker main draw as an amateur at the 2014 Wuxi Classic, then faced Neil Robertson at the 2014,^[1][2] and Mark Selby at the 2015 UK Championship.^[3] He won four events on the 2017–18 English amateur tour.^[4]

Ahead of the 2018–19 season, O'Connor defeated Brandon Sargeant 4–1 and then Oliver Brown 4–0 to secure a two-year professional tour card for the first time at the 2018 EBSA Play-Offs at the English Institute of Sport in Sheffield.^[5] In June 2018, he beat Andrew Norman 10–3 to become the English Amateur Champion before turning professional.

Professional

On 28 November 2018 O'Connor defeated world number 12 Ryan Day 6–2 in the first round at the 2018 UK Championship.^[6] In February 2019 he defeated top 10 players Kyren Wilson, Ding Junhui and John Higgins en route to his first ranking event semi-final at the Welsh Open,^[7] eventually losing 6–2 to Stuart Bingham.^[8] In the 2021 German Masters he made it to the quarter-finals,^[9] but he lost 5–1 to Tom Ford.^[10]

In December 2022 O'Connor reached his first ranking final at the 2022 Scottish Open, defeating Zhao Xintong, Ding Junhui, Mark Williams, Ricky Walden and Neil Robertson throughout the tournament.^[11][12] However, he lost 9–2 to Gary Wilson.^[13]

In February 2023 O'Connor made it to the quarter-finals of the Welsh Open,^[14] but lost 5–4 to Pang Junxu,^[15] then he defeated number one seed Mark Allen at the Players Championship,^[16] before bowing out to Ali Carter at the semi-final stage.^[17] In April he lost 8–10 to Andrew Higginson in the qualifying rounds of the World Championship. In November, he beat Stephen Maguire to qualify for the last-32 of the 2023 UK Championship.^[18]

On 29 February 2024, O'Connor compiled his first maximum break, the 200th maximum in competitive snooker, during a 3-2 win against Elliot Slessor in the Championship League in his home town of Leicester.^[19] He won his group and made it to the final in the Winners' Group, but there he lost 1–3 to Mark Selby.^[20] In April 2024, he qualified the 2024 World Snooker Championship with a 10-8 win over Matthew Selt for his debut appearance at the Crucible Theatre where he was drawn against Mark Selby.^[21]

Ranking finals: 1

Outcome	No.	Year	Championship	Opponent in the final	Score
Runner-up	1.	2022	Scottish Open	Gary Wilson	2–9

Non-ranking finals: 1

Outcome	No.	Year	Championship	Opponent in the final	Score
Runner-up	1.	2024	Championship League	Mark Selby	1–3

Amateur finals: 1 (1 title)

Outcome	No.	Year	Championship	Opponent in the final	Score
Winner	1.	2018	English Amateur Championship	Andrew Norman	10–3