Daniil Medvedev dropped his first set of the tournament, but advanced to the semi-finals of the US Open with a 6-3 6-0 4-6 7-5 win over Botic van de Zandschulp.
The Russian number two seed breezed into the quarter finals without dropping a set. That perfect run came to a halt as Van de Zandschulp took the third set, but it proved to be a minor blip as he rallied to dispose of his opponent in two hours and 22 minutes.
Van de Zandschulp showed flashes of quality, but they were not enough against a player viewed as the biggest obstacle to Novak Djokovic completing the calendar Grand Slam.
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Medvedev raced out of the blocks, and an opening break of serve put the world number 117 on the back foot.
The Russian’s clean hitting from the baseline overwhelmed Van de Zandschulp early on, and it came as a surprise when the Dutchman worked a break point in the eighth game.
He earned it following a punishing rally, and one shot later Medvedev dumped a backhand slice into the net.
Van de Zandschulp played a couple of glorious passing shots in the following game, but Medvedev steeled himself to break back and wrap up the opening set.
The underdog won a four-hour, 20-minute epic against Diego Schwartzman in the previous round and those efforts appeared to take a toll as his movement began to falter.
After Medvedev raced through the second set to love, Van de Zandschulp called on the trainer for treatment on his legs.
The trainer's magic hands did their job as Van de Zandschulp came out swinging at the start of the third set. He broke serve and took advantage of a drop in level from Medvedev to take the set.
There were 13 unforced errors from Medvedev in the third set, and Van de Zandschulp took confidence from being able to worry the Russian.
The fourth set became a battle, but Medvedev limited the errors and he eventually secured the telling break in the 12th game to wrap up the win.
Medvedev's serve was extremely solid in the fourth set, and the quick service games piled pressure on Van de Zandschulp.
The Dutchman staved off a match point in the 10th game, but two games later the Russian took advantage of a double fault to book his place in the last four.
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