Australian Open qualifier Aslan Karatsev has continued his stunning run through the tournament, advancing to the semi-finals after defeating Grigor Dimitrov in four sets.
The Russian world No.114 pulled off his latest upset after Dimitrov, who was the 18th seed, was hampered by a back problem after winning the first set 6-2.
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Dimitrov was on top early in the second frame before Karatsev stormed back into contention, winning the next three sets in convincing fashion.
Karatsev's victory made him the first player to make it to the final four on their grand slam debut in 53 years.
The 27-year-old Russian will face one of countrymen Andrey Rublev or Alexander Zverev in the semi-finals, saying it was an 'incredible' feeling.
"It's an unbelievable feeling, of course. The first time playing a main draw, first time playing the semis. It's incredible," Karatsev said.
"It was a really tough one at the beginning for me, to hold the nerves, and it was really tricky. The heat was too much.
"I tried to play in the second set. I tried to find a way how to play, and then in the third set it felt better."
Karatsev he didn't notice Dimitrov was hampered by his back problem until the Bulgarian star's serve slowed to just half its normal pace.
The rising star's performance earned him plenty of plaudits on social media.
Aslan Karatsev has beaten Grigor Dimitrov to become the first man in the Open Era to reach the semi-final stages on his Grand Slam debut.
He is also the lowest-ranked man (114) to reach a Grand Slam semi-final since Goran Ivanisevic in 2001.
Some achievement! 👏👏👏#AusOpen pic.twitter.com/F7QTCWssZy
— Oddschanger (@Oddschanger) February 16, 2021
Simply Incredible : World nr 114 Aslan Karatsev is though to his 1st ever Grand Slam Semi-Final #Ausopen. He is definitely fulfilling my prediction some days ago. Love an underdog doing well! https://t.co/AgjoNRovZH
— Sunday Oliseh (@SundayOOliseh) February 16, 2021
➡️Ranked #253 after the pandemic break
➡️Qualified in Doha
➡1st *ever* player to reach the SFs on his Grand Slam debut
➡️5th ever qualifier to reach a Slam SF.
➡️ Will rise to inside the top 50 next Monday.
One of the best stories in recent years pic.twitter.com/WzJ63tHCmp
— José Morgado (@josemorgado) February 16, 2021
Wow. Russia's Aslan Karatsev becomes the first man in the Open Era to reach the semifinals on his debut in Grand Slams. Also just the fifth qualifier to do it in the Open Era and the first at the #AusOpen since 1977.
— Ashish Magotra (@clutchplay) February 16, 2021
Tsitsipas' armchair Open ride may be over
If not for Thanasi Kokkinakis, Greek showman Stefanos Tsitsipas would barely have raised a sweat on the way to his Australian Open quarter-final showdown with history-chasing Rafael Nadal.
The No.5 seed dropped a total of just 10 games in his first and third-round wins over Gilles Simon and Mikael Ymer.
And he didn't even get to set foot on Rod Laver Arena on Monday night after his fourth-round opponent and No.9 seed Matteo Berrettini withdrew with an abdominal strain.
So if Nadal is looking for any recent pointers on how best to stretch Tsitsipas he would be well advised to study the second-round clash at Melbourne Park where Kokkinakis was just shaded in a five-set thriller stretching over four and a half hours.
The Spanish world No.2 pulled out of the ATP Cup earlier this month with a back injury.
Nadal's form and fitness have both improved as the Open has progressed, and he rated the opening set of his fourth-round win over Italian Fabio Fognini as the best tennis he has played this year.
"That's normal because I was able to practise for two days in a row," said Nadal.
"That makes an important difference.
"But at the same time it's important to find positive feelings now.
"My physical condition needs to keep improving but I think this match (against Fognini) helps, too.
"I was not able to practise the proper way for the last 19 days, but yesterday I started again to increase the amount of work on the practice court and today has been a positive victory with some long points."
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