Masters 2018: Mark Allen beats Ronnie O'Sullivan at Alexandra Palace

Defending champion Ronnie O'Sullivan said he was "glad" to be out of the 2018 Masters after he lost 6-1 in the quarter-finals to Mark Allen.

O'Sullivan, 42, has been struggling with illness during the competition at Alexandra Palace in London.

"It is not much fun when you go out there and am not feeling great," O'Sullivan told BBC Radio 5 live.

Northern Ireland's Allen, who is into the last four for a third time, will play either John Higgins or Ryan Day.

"I was feeling 60% and was hoping Mark would make some mistakes," added O'Sullivan. "I didn't feel good enough physically to go on and win the tournament anyway.

"I'm glad it is over. I don't make excuses and I had to show up, if I was a footballer I would probably have missed this game but it is an individual sport so you have to turn up."

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Despite thrashing Marco Fu 6-0 in the opening round on Tuesday, O'Sullivan claimed he had not been well during that match saying he felt "very dizzy" and had "double vision" and said he felt the same against Allen.

"I'm struggling, I don't know what it is, a virus or something and I was having dizzy spells," said O'Sullivan.

"It was a tough match for me. I can just rest up and get ready for my next event. Mark deserved his win, I didn't give him much to make him struggle. You have to give people credit and he had a fantastic performance."

O'Sullivan, 42, took the opening frame with a break of 75 but Allen made breaks of 65, 115 and 85 to hold a 3-1 lead at the mid-session interval.

World number eight Allen made a score of 81 in the fifth, before taking the next two frames to seal his victory.

"Ronnie is the benchmark in this game and I'm very happy," said the 31-year-old. "I scored very well up to 4-1 and kind of fell over the line. Against Ronnie I play more aggressive as you get less chances.

"I'm not getting carried away, it is one match and there are two very tough ones ahead of me if I'm going to win. I came here to win the tournament and if I go home without the trophy then I'm very disappointed.

"I will get so much confidence from that. He missed a few because I put him under pressure. I haven't won a tournament in nearly two years and I'm looking to put that right. If I don't win one of these big tournaments I will be very disappointed."

Two-time Masters champion Higgins plays Day in Friday's quarter-final, with the winner of that tie facing Allen in the semi-final on Saturday.

Analysis

Six-time Masters champion Stephen Hendry on BBC Two:

It doesn't matter who you are, if someone keeps pumping out one-visit victories then you can't do anything, when you are under pressure, you are under pressure.

Ronnie was just totally outplayed and Mark Allen did what he had to - he was very impressive."

Ronnie O'Sullivan has won the Masters in 1995, 2005, 2007, 2009, 2014, 2016 and 2017 - a record seven times

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