revealed that he has a unique nickname for after watching his rival's defeat against Ben Woollaston extend into the early hours. A was from Leicester in a surprise first-round exit.
An epic contest at The Crucible ended with Woollaston securing a shock 10-8 victory over the four-time champion. The lengthy bout lasted for hours, and the final frame itself went on for 46 minutes. Selby initially looked likely to make the score 9-9 before Woollaston mounted a comeback. The match finally finished at eight minutes past midnight.
The often lengthy nature of Selby's matches has prompted O'Sullivan to dub the 41-year-old 'midnight Selby'. He revealed that players do not want to be scheduled after the Leicester cueist because they anticipate having to wait until the next day to play.
Speaking to TNT Sports, O'Sullivan joked: "I call him 'midnight Selby' because his games go past midnight every night. He's a nightmare! You don't want to be following Mark because you're going into the next day."
Selby brutally branded his own performance "pathetic" and insisted he was the cause of his own downfall.
"I didn't deserve to win," Selby said. "Ben played some great stuff, his safety was unbelievable at times but I still had my chances. It was pathetic really from me, to play like that is disappointing.

"It's the same old story, I try too hard and stop myself from playing. I love Ben to bits, I've known him for years. I grew up with him and have seen him progressing."
Selby is usually a calm character at the baize, but he allowed his emotions to get the better of him in a tight and tense match. After losing the 13th frame, he threw the yellow ball to the other end of the table in a rare display of emotion.
In a separate interview, Selby admitted: "I just felt like I threw so many frames away. I kept getting 30 in front and running out of position or missing a silly shot. Ben would come back and win the frame. I probably threw five or six frames away. Just disappointing, you know, because I came here with a bit of confidence and I didn't expect to play like that."
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