Being around Daniil Medvedev and Andrey Rublev has clearly helped Aslan Karatsev. The Russian qualifier, playing just his 16th tour-level match and maiden major championship, didn’t blink on Friday in his first match against a member of the Top 10 in the FedEx ATP Rankings.

The World No. 114, who Medvedev described last week as Russia’s “secret weapon” in the nation’s ATP Cup title-winning run, overpowered eighth-seeded Argentine Diego Schwartzman with 50 winners in a 6-3, 6-3, 6-3 victory for a place in the Australian Open fourth round.

“It’s an unbelievable feeling, I qualified so I was already very happy,” said Karatsev. “I’ve had a lot of worries over the past few years, so I am relieved, overjoyed to be at this stage. I had a big knee injury a few years ago, so to be here and represent Russia at the ATP Cup last week really gave me confidence.”

Karatsev was outside of the Top 250 in March last year, but following the ATP Tour suspension due to the COVID-19 pandemic, the 27-year-old won 18 of his final 20 matches on the ATP Challenger Tour. He will now prepare to face a Canadian: No. 11 seed Denis Shapovalov or No. 20 seed Felix Auger-Aliassime at Melbourne Park.

Karatsev had one break point for a 4-0 lead against Schwartzman in the first set, which saw the Russian qualifier lose just three first-service points and hit 13 winners. After saving two break points at 0-1 in the second set, Karatsev didn’t blink and struck back-to-back forehand winners to seal the set.

Schwartzman broke Karatsev’s serve at the start of the third set, but it was only a temporary reprieve. Karatsev saved 10 of 11 break points and completed a memorable win with his ninth ace on John Cain Arena.

“He was playing amazing tennis,” said Schwartzman. “I didn’t serve well [and] maybe that was one of the keys in the match, because he was really comfortable [hitting] returns… He was doing everything really well, moving well, hitting well, and I was not really comfortable in the match. I think he deserved to win.”

Four years ago, Karatsev was sidelined for six months after picking up a knee injury, which he suffered while training in Spain. Today, Karatsev is just the fifth qualifier in 21 years to reach the fourth round of a Grand Slam championship.