Ronnie O'Sullivan overcame Barry Hawkins and a bout of the "twitches" to complete a 6-4 win in the Players Championship semi-finals at the Marshall Arena in Milton Keynes.
Less than 24 hours after he produced a majestic display in a 6-1 drubbing of Jack Lisowski in a quarter-final lasting only 78 minutes, O'Sullivan was forced to scrap his way to victory against Hawkins having looked all at sea in falling 3-0 behind to the man he defeated in the 2013 world final.
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"I was waiting around all day. It felt like forever and I thought I was going to play useless tonight," said O'Sullivan, who will meet John Higgins or Kyren Wilson in Sunday's final.
You have all those thoughts going around your head.
"If you start struggling, you feel like you have wasted a day. It was a struggle at the start.
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"I had some chances. Barry played well, every credit to him, but I just had to hang in there.
Even towards the end, I thought I was going to miss something. I was getting really tight in the end and twitching. It was horrendous, the twitches.
"It'd be great to win on Sunday. I'm pleased I've got a day off. I don't know if the nine-mile run had an effect, but I'm not going to stop. It's the best thing in my life at the moment," he added.
"I was twitching there at the end and Barry should have had me. I got lucky there."
Hawkins, who completed a 6-2 win over 2015 world champion Stuart Bingham in the last eight, edged an error-strewn opening frame before breaks of 109 and 87 saw him gallop 3-0 clear of the world number two.
O'Sullivan stemmed the tide by winning the fourth frame and further timely knocks of 83, 75, 90 and 79 saw him reel of four straight frames for a 5-3 advantage.
An 81 by Hawkins extended the match to a tenth and penultimate frame with the world number 18 narrowly failing to gain position on the final three reds in baulk.
It proved a pivotal error as a safety mistake moments later saw O'Sullivan return to the table to clear up and pinch the frame and final spot by only four points on the black.
"Barry is a class act, and plays a great game. He's a fantastic player. I just had to grind it out to stay in there," said the 37-times ranking event winner, who lost 9-8 to Jordan Brown in the Welsh Open final last Sunday.
"The continuous tournament keeps going."
O'Sullivan could face old rival Higgins for the first time in a ranking event final since the 2005 Grand Prix with the four-times world champion dismissing Mark Selby 6-0 in the final quarter-final on Friday.
Higgins faces Kyren Wilson in the second semi-final on Sunday evening.
"I don't want to be having wars and tough matches," said O'Sullivan, who has equalled Stephen Hendry's record of appearing in 57 ranking event finals.
"I want to go out and play half decent. I was watching Selby and Higgins today, and I struggle to watch that because that's not the way I want to play snooker.
I haven't got the stamina or the energy to want to tough them games out. It felt a little bit like that tonight and this is what match snooker is. It is hard. You want to go out and enjoy yourself with the result becoming secondary.
"Why am I putting myself through the grind? I was feeling it. It's tough."
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