Nick Kyrgios heaps praise on Jannik Sinner, says he "never played someone who hit the ball as hard" as the Italian

Australian tennis star Nick Kyrgios has said he has never played against someone who hits the ball as hard as 20-year-old Jannik Sinner. The Italian has wowed the tennis world with his style of play and maturity on the court over the past few seasons, climbing to the brink of the world's top 10.

Sinner has won four ATP singles titles in 2021 -- Antwerp, Sofia, Washington and Melbourne -- to climb to a career-high No. 11 in the rankings and cement his status as one of the brightest young talents in the sport.

On Wednesday, the Italian defeated big-serving American Reilly Opelka 6-4, 6-2 to advance to the second round of the Erste Bank Open in Vienna. The win was the Italian's ninth consecutive win indoors, having won the title in Antwerp last week.

Sinner's emphatic performance against Opelka was complimented by tennis journalist Ben Rothenberg, who highlighted that the Italian has not lost a set in his last nine matches indoors.

Kyrgios was quick to respond to Rothenberg, praising Sinner's ball-striking ability. Kyrgios referred to his doubles clash at the Citi Open in Washington in August, when he and partner Frances Tiafoe went down to Sinner and Sebastian Korda 6-4, 6-4 in the quarter-finals.

"He is another level. That’s for sure, played him in Washington doubles. Never played someone who hit the ball as hard," Kyrgios tweeted.

Nick Kyrgios of Team Europe on Day 2 of the 2021 Laver Cup at TD Garden on September 25, 2021 in Boston, Massachusetts

Jannik Sinner edges closer to Turin berth

Jannik Sinner at the 2021 US Open in New York

Jannik Sinner, who is a frontrunner for one of the last two spots in the ATP Finals, will take on local favorite Dennis Novak in the second round in Vienna on Thursday.

Sinner is currently in 10th place in the Race to Turin. The fact that No. 8 Rafael Nadal has opted out of the rest of the season due to a foot injury will boost the Italian's chances of earning a spot in the season-ending event.

Novak Djokovic, Daniil Medvedev, Stefanos Tsitsipas, Alexander Zverev, Andrey Rublev and Matteo Berrettini have already booked their spots in Turin. Norway's Capser Ruud, who is also through to the second round in Vienna, is in seventh place while Hubert Hurkacz, who was knocked out in the first round, is in ninth.

If Sinner reaches the semi-finals in Vienna this week, he will replace Hurkacz in the ninth spot (effectively the 8th spot with Nadal being out) in the Race to Turin.