Ronnie O'Sullivan has claimed he 'wanted to kill' former coach Del Hill back in 2004.
The snooker star is always open and honest about a range of subjects and is currently in the spotlight amid a new Amazon documentary.
Speaking on the Stick to Football podcast, O'Sullivan sat down with the likes of Roy Keane, Jamie Carragher and Gary Neville.
He opened up on when he saw Hill assisting Graeme Dott ahead of the 2004 World Championship final.
Ronnie O'Sullivan pictured in 2004 after winning the World Championship
And O'Sullivan has now revealed he was livid at Hill for helping his rival.
"It wasn't that he was coaching another player [...] he had three or four players at the Crucible and they all got beat then he disappeared," he said.
"I didn't see him for 10 days and then 10 minutes before the final he's getting the balls out for the fella [Dott] that I'm playing."
Addressing Keane, he added: "You know, I recognise a bit of myself in Roy,' he told Keane.
"I wanted to kill him, I want it to have it, you know.
"I was fuming. I thought: 'How could you do that to me?' I was gutted."
When quizzed on why he decided to do the documentary on Amazon, The Rocket continued: "I’m still playing and thought it would be easier to do a documentary while I was playing, so they can follow me whilst still playing.
"I thought it was quite a bit of a buzz to have someone follow me, trying to win the World Championships.
"So it was a way of incentivising myself to get motivated enough to make me get in the Roy Keane mode of 'Come on, let’s have it!'
"Once I'd let the cameras in, I wasn't going to crumble and give a half-hearted display.
"I knew I had to give 100 per cent because I knew I was going to have to watch it back and I didn't want to defraud the public.
"At first, I was [thinking about being mic’d up], but after a while it was just normal.
"I’ve done 17 days of it, playing every match and every session.
"I was aware that they were recording everything I said, but I knew they weren’t going to put something that would get me into trouble."
While speaking to the footballers, O'Sullivan also opened up on the 'worst time of my life'.
He said: "I had so many faults and I played players that could be ranked 30 in the world, but if he played to certain level I thought I could not beat him.
"I was just too in and out and he was consistent.
"That was a really bad low for me, I knew I could not win the big ones and that felt really bad for me.
"I knew if I could get some consistency together with my ability then that would not have been an issue.
"So that was horrible, I couldn't handle that, but I was not prepared to really do anything about it.