Quarter-finals made his 1,100th career
century break in his 10–8 win over
John Higgins. The first round of the event was the quarter-finals, held from 22 to 25 March 2021. The first match was held between
Ronnie O'Sullivan and
John Higgins, who had contested the final of the 2021 Players Championship, Higgins winning 10–3. O'Sullivan had won 37 of the 68 matches the pair had competed in since they turned professional in 1992. Higgins won the opening frame with a of 72, before O'Sullivan won the next two frames to lead 2–1. Higgins made the first
century break of the event in frame four, and the pair remained tied at 3–3. O'Sullivan pulled ahead by three frames to 8–5 later in the match, making a break of 112, before Higgins made a 70 break in frame 15 to be one behind 7–8. O'Sullivan then made a break of 101, the 1,100th century break of his career. Robertson won the opening frame, but Lisowski took the second, and later tied the match at 2–2. Lisowski only scored 39 more points over the next four frames, Robertson making two century breaks, and lead 6–2 between sessions. In frame 14, Lisowski made a break of 129, before Robertson won the match 10–5 in frame 15. Robertson claimed that Lisowski would need a "killer instinct" to improve his game going forward. The third quarter-final was held between English players
Kyren Wilson and
Mark Selby. Wilson won the opening frame before Selby made a break of 109 in the second. Selby also won the next two frames with breaks of 81 and 54. Leading 6–2 after the first session, Selby made a of 84 in frame nine, Wilson winning frame 10. The match was the seventh time the two players had met in a professional match, Selby winning all of them. Barring the
Snooker Shoot Out, a one-frame tournament, this was the only event in the season Wilson had not scored a single century break.
Judd Trump met
Barry Hawkins in the last quarter-final. Hawkins won the first two frames with breaks of 70 and 90 before Trump equalled the score at 2–2, making a break of 119 in frame four. The next three frames were won by Hawkins, before Trump took frame eight to trail 3–5. Trump returned with breaks of 64 and 86 before the , and won frame 13 with a break of 86, to trail by a single frame. In a nervy 17th frame, Hawkins won the match 10–7 after potting a long . In the third frame, Selby made a series of errors allowing Robertson to take the frame, and led 4–0 after a break of 77 in the next frame. On the resumption, Robertson made a break of 136, before making breaks of 84 and 103 to lead 9–2. Selby won the next frame, but Roberston took frame 13 to complete a 10–3 victory. Robertson commented "My safety was fantastic, my long game was excellent – probably as good as it has been. I created a lot of opportunities", and cited his form was helped by not competing in some preceding events. The second semi-final was played between O'Sullivan and Hawkins. O'Sullivan had won 15 of the 17 prior professional matches they had contested. Hawkins led the match 3–0, with breaks of 125 and 138, but O'Sullivan won four straight frames to lead 4–3. Hawkins took the final frame of the first session to tie the match at 4–4 with a break of 65. In the second session, O'Sullivan took frame nine, but Hawkins won the next three with breaks of 74, 50 and 103. O'Sullivan won frame 13 to trail 6–7 with a break of 78. O'Sullivan led the final frame 48–0, but Hawkins missed a meaning he required foul shots to win the match. He was unable to score the foul points, allowing O'Sullivan to win the match 10–9. After the match, O'Sullivan suggested that Hawkins deserved to win the match: "I feel for Barry, he's been grafting at his game, and he's been unlucky in a few results. He deserved that victory. It's a horrible way to lose, but hopefully he can respond from that." O'Sullivan won the opening frame, before a century break by Robertson tied the match 1–1. In the evening session, Robertson made breaks of 93 and 75 to lead 6–4 with O'Sullivan making mistakes in each frame. In those four frames, he scored 442 points, to O'Sullivan's 16. Over the evening session, O'Sullivan accumulated only 26 points to Robertson's 650. The loss was O'Sullivan's fifth loss in a ranking final in the season, having never lost more than three in a row previously. He praised Robertson's play after the match, saying "I’ve never seen anyone play as well as that... I can't compete with that." This was Robertson's 20th ranking event victory, ==Tournament draw==