Alex de Minaur has cast aside sentiment to end Cruz Hewitt’s breakout run and storm into the Washington Open quarter-finals.

The top seed and defending champion produced a clinical display to defeat the 17-year-old Hewitt - son of former world No.1 Lleyton - 6-2 6-3 in just 61 minutes.

De Minaur shared a warm embrace with Hewitt at the net as Lleyton looked on from the stands at Stadium Court.

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“It was definitely weird,” de Minaur said. “I knew I was going to play him on the tour some day, but I didn’t actually expect it to be this week. It was an amazing feeling.

A Wimbledon boys’ finalist this month, Hewitt has idolised de Minaur while growing up around the David Cup team captained by his father.

Alex de Minaur and Cruz Hewitt shake hands after their men’s singles match at the Washington Open. Credit: Getty

A humble Hewitt waves to fans after the match. Credit: Getty Images

Before the match many photos of Cruz and Alex resurfaced on social media. Credit: Getty

Immediately ahead of the match, former Australian star and commentator Rennae Stubbs said: “This is a wild moment in Aussie tennis history.”

De Minaur said: “Even all the lead up, seeing all the incredible pictures that we have together and how we’ve grown up, I’m glad I managed to get through.

“But I’m sure we’re going to have many battles in the years to come.”

Australia’s world No.6 charged to the net with authority and displayed great hands en route to improving to 29-14 this season.

Despite his defeat, Hewitt is set to soar some 252 spots in the rankings to a fresh career-high of around world No.360 after qualifying in Washington and then winning his maiden ATP match.

Competing for the first time since marrying British WTA star Katie Boulter this month, de Minaur next faces American Brandon Nakashima, who ousted seventh-seed Jakub Mensik 7-6 (7-5) 3-6 6-4 to reach his second consecutive Washington quarter-final.

Nakashima holds a 2-1 edge over the Australian, with de Minaur’s lone win against the American also coming in last year’s quarter-finals before he went on to lift the title.