Rafael Nadal defeated Frances Tiafoe 6-3, 6-4, 6-2 in just 107 minutes to advance to the Australian Open 219 semis.
Nadal will next play Stefanos Tsitsipas, who knocked out Roger Federer in the fourth round and Roberto Bautista Agut in the QFs.
"For me is always the same: you are in the semi-finals of a Grand Slam, you can't expect an easy opponent," Nadal said.
"Stefanos is one of the best players of the world. To have the chance to be in that final, I need to play my best, and that's what I am looking for."
Tiafoe had shocked fifth seed Kevin Anderson and Grigor Dimitrov, seeded 20, but Rafa proved too formidable for the popular American in his first major quarter-final.
The Spaniard has been in irresistible form in Australia in his first tournament since limping out of the US Open and having foot surgery.
"I feel lucky to be where I am after what I went through to be able to compete at this level," he said.
"That's why I get up in the morning and go to the gym and work hard."
Nadal had never faced the world number 39 before but decided rather than feel his way into the match he would bludgeon Tiafoe from the start.
An immediate break of serve was the result and a controlled romp to the opening set in 31 minutes as he imposed his authority.
He repeated the lesson at the start of the second, continuing a game plan that seemed to be based on overpowering the speedy young pretender by keeping him pinned to the baseline.
"I knew he was going to bring crazy intensity, I knew the ball was going to be jumping," said Tiafoe.
Tiafoe was thrust into the global limelight partnering Serena Williams at the recent mixed teams Hopman Cup and the best Grand Slam performance for the youngster prior to this tournament was third round at Wimbledon last year.
He was bidding to be the youngest American man to make the semi-finals since Andy Roddick in 2003.
The problem was that Tiafoe, who turned 21 on Sunday, was up against the only player in the draw not to have dropped a set.
"I knew if he got hold of a forehand, it was going to be barbecued chicken," said Tiafoe.
"But point in, point out, I've never seen someone so locked in."
Tiafoe finally forced chances to break at 1-2 in the second set, but Nadal twice held out to keep up an amazing run of not dropping his serve since 5-3 up in third set of his first round tie against James Duckworth.
He broke Tiafoe again in the first game of the third set to end any fading hopes that the American could mount a comeback.
If Nadal wins his 18th Grand Slam title in Melbourne to move two behind Roger Federer he will create his own slice of history.
His second Australian Open crown would make him the first man in the Open-era, and only the third of all-time along with Roy Emerson and Rod Laver, to win each Grand Slam on two or more occasions.
Article from AFP
