Raymond van Barneveld admitted he is struggling with his diabetes despite booking his place in the quarter-finals of the World Championships at the expense of Kevin Painter, winning 4-1.

The number two seed now faces Ronnie Baxter, who beat Colin Lloyd 4-1, in the last eight, and is a strong 1/2 favourite to progress, with The Rocket available at 6/4 to make it to the semi-finals.

Barneveld had looked on course for another clean sweep after taking a three-set lead but clearly struggled in the fourth, only to come back with renewed vigour after a break to seal his passage.

“In the fourth set I was really tired,” he told Sky Sports. “In August I found out I had diabetes and I can’t handle it.

“For some reason it’s there and you are so tired. I’m so tired every single time and I’m not playing my game. I’m pleased with the doubles but the treble 20’s are really poor this week, really poor.”

James Wade was pushed all the way in a see-saw clash with Andy Hamilton and could have been knocked out only for the Hammer to miss double 18, going for a 156 check-out.

That chance came in the fourth-leg of the deciding set and Wade went on to wrap the next three legs to book his place in the quarters where he will face Simon Whitlock, who had earlier seen off Terry Jenkins 4-2.

Wade is the 4/6 favourite to make his number three seeding count, with the Wizard of Oz available at 11/10 to continue his fine run of form.

Co Stompe (5/6) will play Mark Webster (5/6) in the last eight, while world number one Phil Taylor is a strong 1/6 favourite to continue his march towards a 15th world title against in-form Adrian Lewis, who is available at 7/2.