Tien upsets Medvedev, joins Michelsen to make history at 2025 Australian Open

Qualifier Learner Tien achieved more than a personal milestone when he stunned Daniil Medvedev in the early hours of Friday morning at the 2025 Australian Open. With his 6-3, 7-6(7), 6-7(8), 1-6, 7-6(10-7) victory over the world No. 5 and three-time Melbourne finalist, the 19-year-old joined compatriot Alex Michelsen in the third round to make American tennis history.

Tien and the 20-year-old Michelsen, who upset former finalist Stefanos Tsitsipas in the opening round, are the first pair of U.S. men age 20 or younger to reach the third round at a Grand Slam event since the 2003 US Open (Andy Roddick, 20; Robby Ginepri, 20) and at the Australian Open since 1990 (Pete Sampras, 18; David Wheaton, 20). Tien is also the second-youngest American man to reach the third round at the Australian Open after Sampras in 1990.

Tien, from Irvine, Calif., and Michelsen, from Laguna Hills, Calif., are longtime friends and have trained together since 2021. They recently competed in the semifinals of the Next Gen ATP Finals, with Tien winning in five sets at the Jeddah youth showcase in December.

Tien takes out Medvedev for first Top 5 win

In a nearly five-hour match, Tien missed out on a match point in the third-set tiebreak before regrouping to prevail in a dramatic final set. He saved three break points in the opening game of the final frame before twice trading breaks with Medvedev down the stretch. Tien surrendered a 3-1 advantage early in the fifth set, then later denied Medvedev's attempt to serve out the match after being broken at 5-5.

Down a mini-break at 6-7 in the decisive tiebreak, Tien won four straight points to clinch victory, finishing the set with 13 winners.

"I was definitely hoping it wouldn't go to a fifth-set breaker, but I'm just happy to get a win,” said the American, who is set to break into the ATP's Top 100 behind his Melbourne run. “I know I made it a lot harder than maybe it could have been... Losing the third was tough after playing for that long and having a match point. I didn't even get to touch the ball I don't think, it was an ace. So it was a little disappointing to see a fourth [set] after fighting back from a break down in the third.

Collins, Keys win three-setters to set up R3 showdown

Good friends and childhood pen pals Danielle Collins and Madison Keys will square off in an all-American third-round matchup in Melbourne after both women battled to three-set victories on Thursday. Collins was a 7-6(4), 4-6, 6-2 winner against Aussie qualifier Destanee Aiava, while Keys beat Romanian qualifier Elena Gabriela-Ruse, 7-6(1), 2-6, 7-5.

Thriving in front of the partisan, pro-Aussie crowd, the 10th-seeded Collins dominated the final set to defeat the home favorite.

"I've been doing this my whole life. I love playing in a crowd that has energy, regardless of what side they're on," she said. "It just motivates me even more... I think it really helped me in the end. Just helped me concentrate more and challenged me at times. Just pushed me through the finish line."