Ronnie O'Sullivan has said that he felt ill during his defeat to James Cahill in the first round at the World Snooker Championship.
O'Sullivan, the world number one and five-time world champion, lost 10-8 to Cahill on Tuesday.
It is the biggest upset in the history of the tournament. Cahill is a 23-year-old amateur who won three qualifiers to reach the first round at the Crucible. He is the first ever non-professional to play at the World Championship.
"All my limbs just feel really heavy," O'Sullivan told BBC following the match.
I had no energy, I was struggling to stay awake, I just feel horrendous to be honest. I have not slept brilliantly the past couple of nights.
You have to come here feeling physically and mentally good, I felt mentally good but if you're physically not 100%, it's going to make it hard.
I haven’t felt great for a few weeks. He did well. He held himself together.
It’s been a very successful season for me, but it wasn’t meant to be.
"I could barely stand up at the end," said Cahill.
"I am not really sure what to say.
"I scored a good pressure 70 to go 6-5 up and after that I felt like he was the one under pressure. He didn't want to lose to me.
"I have always believed in myself and that I can beat anyone on my day. I want to show what I can do now."