Four-time world champion Mark Selby sailed through the first round of the UK Championship with a 6-2 victory against Ross Muir before admitting he agrees with Shaun Murphy's criticism of amateurs playing in professional events.

Murphy, a former world champion himself who has banked over £4m in career prize money, was bundled out of the tournament in York at the first hurdle by 19-year-old Si Jiahui, who is playing as an amateur after dropping off the tour at the end of last year.

After his shock 6-5 loss, the 39-year-old launched an extraordinary tirade against World Snooker Tour for allowing players like Si to compete via the 'top-up' system, in which the top-ranked players outside the tour gain entry if the 128 available professional slots cannot be filled.

Murphy was roundly criticised on social media for his opinions and World Snooker chiefs dismissed his claims.

However, Selby has vowed to "stand by" Murphy and after his win against Muir he told BBC Sport: "I think a lot of players agree with him.

"Because he [Shaun Murphy] said it after he lost, people probably think it is sour grapes and he wouldn't have said it if he had won - but I totally stand by everything he said.

"There's a reason there is a Q School to try to get on [the professional tour], and if you don't get on, you should have to wait another year and play in the amateur events."

Aaron Hill beaten by Noppon Saengkham at UK Championship

Selby's success against Muir included breaks of 67, 93 and 95, while Mark Williams made two century breaks as he defeated China's Lei Peifan 6-3.

Gary Wilson made his fourth career maximum break en route to a 6-2 win against Ian Burns.

The former world semi-finalist achieved the feat in the sixth frame of the match and it puts the 36-year-old in line for the tournament's £15,000 high-break prize.

Wilson's 147 is already the fourth main draw maximum of the new season, and follows Mark Allen's similar achievement against Si Jiahui at last month's Northern Ireland Open.

Ronnie O'Sullivan made a superb 139 clearance in the opening frame of his victory over amateur Michael White.

Despite the flying start, O'Sullivan was made to work for his win by the Welshman, who levelled up the match at 3-3 before the six-time world champion reeled off three consecutive frames to win 6-3.

China's Ding Junhui made a break of 129 on the way to a routine 6-2 win over his compatriot Anda Zhang, while Thailand's Thepchaiya Un-Nooh made five century breaks as he comprehensively outclassed seven-time former world champion Stephen Hendry 6-1.

David Gilbert put together a break of 131 in an equally convincing 6-1 victory against Alfie Burden and Barry Hawkins was also a 6-1 winner against women's world champion Reanne Evans.