Ricky Walden and Jamie Jones to reach the final, then defeating Ronnie O'Sullivan 9–3 to claim his 19th ranking tournament win. The following week, Selby reached the semi-finals of the World Grand Prix, where he was defeated 4–6 by Jack Lisowski, despite compiling the highest break of the tournament, a 143 in the seventh frame of the match. He reached the final of the Snooker Shoot Out in February but his early 24-point lead was eclipsed by Ryan Day's 67-point winning break in the last four minutes of the match. Aiming to secure a record 12th successive ranking final win, Selby expressed doubts about whether the Shoot Out should be classed as a ranking event. Afterwards, he exited both the Welsh Open and the Players Championship at the quarter-final stage, then the Tour Championship with one more semi-final defeat by Robertson, repeating his last year results for all three events. Selby won his fourth world title in May 2021, defeating Shaun Murphy 18–15 in the final of the World Championship in front of a capacity crowd at the Crucible Theatre. He became one of only five players to have won the championship four or more times at the Crucible, and said in his post-match interview: "to win it four times is something I could only have dreamed of." 2021–22 season In contrast with his last two snooker years, this was a poor season for Selby. His first tournament was the British Open. He was defeated in the second round, but returned to the top of the rankings for the first time since March 2019. After that, he suffered many early round exits, failed to qualify for tournaments or has withdrawn from them. Selby said that snooker seemed "irrelevant right now" to him, as he spoke about his struggles with depression that was affecting his life and snooker form. He reached the semi-finals of the World Grand Prix in December though, but after levelling the match at 2–2, he was defeated 3–6 by Neil Robertson. The only other highlights of the season were his quarter-final appearances at the 2021 Champion of Champions, where he made his 700th century break in his opening match against David Gilbert, becoming the sixth player to reach that milestone, and the 2022 Masters, where Selby avenged his 6–3 loss to Stephen Maguire from last year's tournament by beating the Scotsman by the exact same scoreline, but