Selby eases past Milkins to set up Masters quarter-final against Allen
Selby barely looked troubled as he raced to a 4-0 lead at Alexandra Palace on Wednesday evening, before he missed a regulation pot in the fifth frame to allow Milkins back on the table.
Milkins duly clawed one back but that was as good as it got for him as he lost the following two frames to confirm his exit from the tournament.
Selby's victory means he will take on Allen in the quarter-finals after the Northern Irishman beat John Higgins 6-5 on Wednesday afternoon in a thrilling match that went to a final-frame decider.
"I felt good before the start of the match. The last few days I feel like I've been hitting it OK," Selby told the BBC.
"It's nice to actually put that performance - what I've been playing like on the practice table - out here on the match table."
Selby won the last of his three Masters titles in 2013, struggling to match that form in the decade that has followed.
"It's an amazing venue to play in," he said of Alexandra Palace. "Unfortunately for me I've not managed to stay in the tournament too long the last few years, but I played OK today.
"The crowd's been amazing all week, not just for this match but for every single match. I can't wait to start the next game.
"Mark's obviously a class act, (he) made a fantastic break in the decider earlier on against John. It doesn't get any easier for sure."
The other quarter-finals see Ronnie O'Sullivan take on Barry Hawkins on Thursday afternoon, followed by Shaun Murphy against Jack Lisowski. Selby's match against Allen then takes place on Friday evening, after the match between Judd Trump and Ali Carter.