Defeat for Trump was the first time he had failed to make the second round in Sheffield in seven years and the loss clearly hurt as he declined media interviews, for which he could be fined by World Snooker.

McLeod, priced at 1,000/1 to win the title by some bookmakers at the start of the competition, was delighted to cause an upset against the joint-tournament favourite.

"It's my best win of my career," he said. "To beat Judd Trump on centre stage is brilliant.

"I've always known I'm capable, it's actually doing it.

"We can all say, 'Yeah I'm brilliant and I can do it', but it's actually producing when you need to. I've done it today."

McLeod, 46, was made to wait for his moment of glory as, at 9-7 up, the match was halted on Wednesday afternoon due to a scheduling conflict and then completed in a third session during the evening.

The delay resulted in an agonising few hours for the world number 54.

"I was sweating, my mind was going all around trying to work out scenarios of how I'm going to do it," he added.

"It just doesn't work, you've got to try and quieten your mind. It's a headache. Judd's quite capable of pinching three frames in a row."

There were rumours during the match that 2011 runner-up Trump was suffering with a possible shoulder problem.

The 27-year-old from Bristol was regularly seen grimacing during the afternoon session, however McLeod was keen to focus on his triumph rather than any issue for his opponent.

"When he was 4-0 up, he didn't look injured to me," said McLeod, who will face Stephen Maguire in the next round.

"He was potting balls from everywhere.

"What can I do? I've got to deal with holding myself together. Being the oldest player left in the tournament, 46, do we have our aches and pains? Well, maybe we do.

"You've got to look after yourself, ain't you?"

There were also upsets in the other two matches completed on Wednesday as Graeme Dott and China's Xiao Guodong joined McLeod in the last 16.

Dott, the 2006 champion, overcame two-time finalist Ali Carter 10-7, while Guodong knocked out world number 16 Ryan Day 10-4.

Dott, ranked 19 places below his would number 10 opponent, said: "I certainly tried to attack the ball as best I could, when it was necessary.

"I think you've got to do that here, you're playing the best players in the world, you can't go into your shell and just try and tippy-tippy about, it doesn't work.

"I'm not the best at anything but I'm pretty good at everything and over the long games that's all you need to be."

Welshman Day, who will drop out of the top 16 following his defeat, was unhappy with his performance.

"It was a bit of an embarrassing day at the office," he said. "My concentration was poor all day really.

"You want to play well on a big stage and today I didn't."

Elsewhere, 2010 champion Neil Robertson holds a 8-1 lead on Thailand's Noppon Saengkham heading into Thursday's second session, while 2013 finalist Barry Hawkins is 7-2 up on Tom Ford.