Miami - Alexander Zverev remains on target for his third ATP Masters title after dismantling Borna Coric 6-4, 6-4 to set up a meeting with Pablo Carreno Busta for a place in Sunday's Miami Open final.
The German world No 5 produced a supremely solid display and was excellent value for this deserved victory against Coric who was ultimately overpowered and outmanoeuvred.
Zverev, who enjoyed a breakthrough year in 2017 after winning the Italian Open in Rome and the Canada Masters by beating Novak Djokovic and Roger Federer respectively, is keen for more of the same at Key Biscayne.
"The times we played before, he just better than me," said Zverev, who will move to number three in the world if he manages to win Sunday's final.
"I am really happy to have made it through against him. Carreno Busta will be a very difficult match, he's playing really well now.
"It is going to be a big test but I am looking forward to it."
Play was delayed for over an hour because of a problem with the Crandon Park floodlights but when the action finally began, the restless crowd were treated to an absorbing match-up between two of the rising stars of the men's game.
And in the end it was Zverev who emerged victorious after just 84 minutes, executing the perfect balance between pressurising the Coric serve, and comfortably holding his own.
Zverev, 20, had lost both his previous matches against the 21-year-old Croatian, at Cincinnati in 2015 and two years later at the US Open. Yet the German started well in the bid to finally get to the Miami last four after losing at this stage for the previous two years.
With his serve reaching 137 mph, he was able to keep Coric in check while adopting the an aggressive mindset.
Carreno Busta has never played Zverev before. He will head into Friday night's match full of confidence after beating six-seeded Kevin Anderson in a dramatic third set tie-break.
Anderson had saved two match points in the second set but the gleeful Spaniard eventually prevailed, reaching his second ATP Masters semi-final.
It was just his second win over a top 10 player in 23 attempts, and his first over Anderson in five attempts.
"It was an amazing match, no?," said the world No 19.
"I lost last week with him, 7-6 in the third set. And today, well, at the beginning of the match I started to play really well. I was returning good, serving good, being very aggressive.
"I served for the match in the second set, 40-15, and he played some unbelievable points, passing shots, returning really good, winner with his forehand.
"After that it was a really tough mental moment for me. But I continued fighting.
"It's a very important victory for me against him. I am so happy to be in the semi-finals."
Juan Martin del Potro and John Isner will contest the first semi-final on Friday afternoon.
Results on Thursday in the Miami Open WTA and ATP Masters tennis tournament (x-denotes seeded player):
Pablo Carreno-Busta (ESP x16) bt Kevin Anderson (RSA x6) 6-4, 5-7, 7-6 (8/6)
Alexander Zverev (GER x4) bt Borna Coric (CRO x29) 6-4, 6-4
Sloane Stephens (USA x13) bt Victoria Azarenka (BLR) 3-6, 6-2, 6-1
Jelena Ostapenko (LAT x6) bt Danielle Collins (USA) 7-6 (7/1), 6-3