| Result | Tournament |
|---|---|
| Lee Spick defeated Sean O'Neill | 2005 World Championship Snooker |
| Rod Lawler defeated Sean O'Neill | 2005 Welsh Open Snooker |
| Sean O'Neill defeated Leo Fernandez | 2005 Welsh Open Snooker |
| Rory McLeod defeated Sean O'Neill | 2005 Malta Cup Snooker |
| Alfie Burden defeated Sean O'Neill | 2005 Irish Masters Snooker |
| Michael Holt defeated Sean O'Neill | 2005 China Open Snooker |
| Sean O'Neill defeated Patrick Wallace | 2005 China Open Snooker |
| Sean O'Neill defeated Mike Dunn | 2005 China Open Snooker |
| Sean O'Neill defeated Stefan Mazrocis | 2005 China Open Snooker |
| Ben Woollaston defeated Sean O'Neill | 2004 World Championship Snooker |
| Sean O'Neill defeated Andy Lee | 2004 World Championship Snooker |
| Simon Bedford defeated Sean O'Neill | 2004 UK Championship Snooker |
| Rod Lawler defeated Sean O'Neill | 2004 Grand Prix Snooker |
| Kuldesh Johal defeated Sean O'Neill | 2004 Challenge Tour - Event 4 Snooker |
| Sean O'Neill defeated Troy Shaw | 2004 Challenge Tour - Event 4 Snooker |
| Sean O'Neill defeated David John | 2004 Challenge Tour - Event 4 Snooker |
| Sean O'Neill defeated Alex Davies | 2004 Challenge Tour - Event 4 Snooker |
| Steve James defeated Sean O'Neill | 2004 Challenge Tour - Event 3 Snooker |
| Sean O'Neill defeated Craig Taylor | 2004 Challenge Tour - Event 3 Snooker |
| Sean O'Neill defeated Lee Spick | 2004 Challenge Tour - Event 3 Snooker |
| Sean O'Neill defeated Darren Clarke | 2004 Challenge Tour - Event 3 Snooker |
| Sean O'Neill defeated Marvin Aldridge | 2004 Challenge Tour - Event 3 Snooker |
| Sean O'Neill defeated James Croxton | 2004 Challenge Tour - Event 3 Snooker |
| Tom Ford defeated Sean O'Neill | 2004 British Open Snooker |
| Stephen Croft defeated Sean O'Neill | 2003 World Championship Snooker |
| Sean O'Neill defeated Kuldesh Johal | 2003 World Championship Snooker |
| Bradley Jones defeated Sean O'Neill | 2003 Masters Qualifying Event Snooker |
| Sean O'Neill defeated Atthasit Mahitthi | 2003 Masters Qualifying Event Snooker |
| Michael Rhodes defeated Sean O'Neill | 2003 Challenge Tour - Event 4 Snooker |
| Ian Martin defeated Sean O'Neill | 2003 Challenge Tour - Event 3 Snooker |
| Sean O'Neill defeated Carlo Giagnacovo | 2003 Challenge Tour - Event 3 Snooker |
| Sean O'Neill defeated Chris Melling | 2003 Challenge Tour - Event 3 Snooker |
| David McDonnell defeated Sean O'Neill | 2003 Challenge Tour - Event 2 Snooker |
| Sean O'Neill defeated Karl Burrows | 2003 Challenge Tour - Event 2 Snooker |
| Sean O'Neill defeated Leonard de Griffa | 2003 Challenge Tour - Event 2 Snooker |
| Michael Rhodes defeated Sean O'Neill | 2003 Challenge Tour - Event 2 Snooker |
| Sean O'Neill defeated Marvin Aldridge | 2003 Challenge Tour - Event 2 Snooker |
| Stefan Mazrocis defeated Sean O'Neill | 2003 Challenge Tour - Event 1 Snooker |
| Sean O'Neill defeated Gary Lees | 2003 Challenge Tour - Event 1 Snooker |
| Sean O'Neill defeated Mike Hallett | 2003 Challenge Tour - Event 1 Snooker |
| Sean O'Neill defeated Troy Shaw | 2003 Challenge Tour - Event 1 Snooker |
| Sean O'Neill defeated Albert Kenny | 2003 Challenge Tour - Event 1 Snooker |
| Tony Chappel defeated Sean O'Neill | 2002 World Championship Snooker |
| Sean O'Neill defeated Stefan Mazrocis | 2002 World Championship Snooker |
| Sean O'Neill defeated Keith Chalmers | 2002 World Championship Snooker |
| Sean O'Neill defeated Tam Mustafa | 2002 World Championship Snooker |
| Sean O'Neill defeated Les Dodd | 2002 World Championship Snooker |
| Sean O'Neill defeated Lee Bovis | 2002 World Championship Snooker |
| Sean O'Neill defeated Mohammed Sajjad | 2002 World Championship Snooker |
| Ian Brumby defeated Sean O'Neill | 2002 Challenge Tour - Event 1 Snooker |