Alexander Zverev marched into the Mexican Open semi-finals, while Nick Kyrgios continued his impressive run in Acapulco.

Zverev – the second seed – moved through to the final four without dropping a set after accounting for Alex de Minaur 6-4 6-4 on Thursday.

The 21-year-old German star, who is through to his second successive Acapulco semi, fired down 13 aces and won 91 per cent of his first serves against De Minaur.

"It's never easy to play him, especially after last night [against David Ferrer], which was a very emotional match for me and the crowd," Zverev said. "I'm happy to get through."

Winner of the ATP Finals in London at the end of 2018, Zverev will next meet Brit Cameron Norrie for a spot in the decider.

Norrie won through to his maiden ATP 500 semi-final after beating Mackenzie McDonald 6-3 6-2.

Meanwhile, Kyrgios reached his first semi-final since June last year after outlasting Stan Wawrinka 7-5 6-7 (3-7) 6-4 in another thrilling match.

Kyrgios stunned top seed and two-time champion Rafael Nadal on Wednesday and the maligned Australian backed that up on the Mexican hardcourts.

The 23-year-old withstood fatigue, cramp and a hostile crowd to prevail after more than two hours, 30 minutes.

Standing in the way of Kyrgios and his first final since winning the 2018 Brisbane International is John Isner, who saw off John Millman 7-6 (7-2) 6-7 (4-7) 7-6 (7-4).

At the Brasil Open in Sao Paolo, top seed Joao Sousa bowed out in the last 16 following a shock 6-3 6-4 loss against Casper Ruud.

Juan Ignacio Londero – the seventh seed – was also beaten by Hugo Dellien, while Felix Auger-Aliassime and Rio Open champion Laslo Djere progressed.