Michael Chang's influence on Learner Tien impresses victorious Alexander Zverev at Australian Open

“I don’t know what Michael Chang has done with him in the offseason,” said Zverev, who reached his 10th Grand Slam semifinal with a 6-3, 6-7 (5), 6-1, 7-6 (3) win. “Very different than last year, for sure. It was incredible to see how he played from the baseline. I thought he was playing unbelievable."

The pair played two head-to-heads last year, with Zverev winning in the first round at Roland Garros and Tien winning in the Round of 16 at Acapulco, where he reached the quarterfinals as a qualifier.

Tien was a breakout star last year in Melbourne, where he upset three-time finalist Daniil Medvedev in the second round and made it to the Round of 16. He won his first ATP title in Metz and reached the final in Beijing. He also landed the crown at the ATP's Next Gen Finals in December.

This year at the Australian Open, he thumped Medvedev in straight sets to reach the last eight.

Tien was the youngest man since 2015 to reach the Australian Open quarterfinals. He was also the only player outside the Top 10 to make it.

Chang, the 1989 French Open champion, knows what it takes for a young player to beat the odds. He won the title at Roland Garros at the age of 17, which remains the youngest for a male to have won a Grand Slam singles crown.

He started working with Tien last year and was in the young player's support crew at Melbourne Park the last two weeks, offering technical advice and encouragement.

Chang's advice to step up to receive Zverev's second serve helped in the second set, when there was a noticeable turnaround in Tien's return points. But his opponent was too consistent with his first serve throughout the match, upping the pressure with 24 aces.

“He’s always a very calming presence,” Tien said of the 53-year-old Chang. "Offers me a lot of stuff mid-match, especially stuff that maybe I’m not picking up on.

"Obviously (Zverev) played a good match. He was playing pretty well from start to finish, so you know, for portions of the match, I was just trying to stay with him and not let him kind of run away with things.

“So it’s more of that. (Chang) was just giving me little bits of encouragement.”

Tien said he's made a lot of headway since his previous trip to Australia, but is still working to improve his serve and his physicality.

“Physically, I wouldn’t say I’m close to, you know, where I hope to be one day,” he said. "But I think weeks like this are good to test myself. I get a lot of takeaways from winning and losing these matches.

“It just really sets me up to come back — come back and be even better the next time.”

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