Head to Head
| UK Championship | 2017/12/04 13:10 | Mark Williams v Ryan Day | 5-6 |
| International Championship | 2017/10/31 11:30 | Ryan Day v Mark Williams | 2-6 |
| Gibraltar Open 2019 | 2017/08/18 11:30 | Ryan Day v Mark Williams | 0-5 |
| Riga Masters 2017 | 2017/06/25 12:55 | Ryan Day v Mark Williams | 5-4 |
| Championship League Snooker | 2017/02/22 15:20 | Mark Williams v Ryan Day | 3-2 |
| Championship League Snooker | 2017/02/20 17:50 | Mark Williams v Ryan Day | 2-3 |
| Championship League Snooker | 2017/01/11 13:55 | Mark Williams v Ryan Day | 3-1 |
| Gibraltar Open 2019 | 2017/01/09 19:55 | Ryan Day v Mark Williams | 2-3 |
Home History
| The Masters | 2018/01/15 13:05 | Ding Junhui v Ryan Day | 4-6 |
| Championship League Snooker | 2018/01/09 15:00 | Ali Carter v Ryan Day | 3-2 |
| Championship League Snooker | 2018/01/09 13:55 | Tom Ford v Ryan Day | 3-1 |
| Championship League Snooker | 2018/01/09 11:00 | Mark Allen v Ryan Day | 3-0 |
| Championship League Snooker | 2018/01/08 18:55 | Ryan Day v Kyren Wilson | 2-3 |
| Championship League Snooker | 2018/01/08 15:55 | Anthony Hamilton v Ryan Day | 3-1 |
| Championship League Snooker | 2018/01/08 14:00 | Ryan Day v Barry Hawkins | 3-2 |
| Championship League Snooker | 2018/01/05 17:55 | Ryan Day v Mark Selby | 0-3 |
Away History
| The Masters | 2018/01/14 13:10 | Mark Selby v Mark Williams | 5-6 |
| German Masters 2018 | 2017/12/22 10:00 | Matthew Stevens v Mark Williams | 3-5 |
| German Masters 2018 | 2017/12/19 19:00 | Mark Williams v Oliver Lines | 5-1 |
| UK Championship | 2017/12/04 13:10 | Mark Williams v Ryan Day | 5-6 |
| UK Championship | 2017/12/02 13:20 | Mark Williams v Andrew Higginson | 6-2 |
| UK Championship | 2017/11/30 09:30 | Mark Williams v Paul S Davison | 6-0 |
| Gibraltar Open 2019 | 2017/11/26 13:00 | Yan Bingtao v Mark Williams | 8-9 |
| Gibraltar Open 2019 | 2017/11/25 13:00 | Elliot Slessor v Mark Williams | 2-6 |