American teen Learner Tien upsets Daniil Medvedev in Australian Open's second round

Jan. 16 (UPI) -- American teen Learner Tien pulled off the biggest upset so far at the 2025 Australian Open, ousting Russian Daniil Medvedev -- the No. 5 player in the world -- in a 4-hour, 49-minute thriller at Margaret Court Arena.

The match started Thursday, but stretched into Friday in Melbourne, which is 16 hours ahead of Eastern time in the United States. Tien, ranked No. 121, converted 9 of 15 break point chances. Medvedev converted just 10 of 24 break points opportunities.

"I know I made it a lot harder than maybe it could have been, but whatever," Tien, 19, said on the ESPN broadcast.

Medvedev held advantages of 20-7 in aces, but totaled 82 unforced errors, compared to Tien's 79. Tien totaled 53 winners, compared to Medvedev's 52 in the 6-3, 7-6(4), 6-7(10), 1-6, 7-6(7) victory.

Tien converted the last four points of the fifth-set tiebreak of the match, which lasted until nearly 3 a.m. local time. He became the second-youngest American man to reach the third round, following Pete Sampras, who was 18 when he did it in 1990.

"I was definitely hoping it wouldn't go to a fifth-set breaker, but I'm just happy to get a win," Tien said.

Tien will play No. 69 Corentin Moutet of France in the third round. Tien lost in the first round in all three of his previous Grand Slam singles appearances, which all came at the U.S. Open.

No. 4 Taylor Fritz, No. 20 Ben Shelton, No. 8 Emma Navarro and No. 11 Danielle Collins were among the top Americans to advance to the third round of the 2025 Australian Open through wins Thursday in Melbourne.

No. 16 Frances Tiafoe suffered an upset.

"I'm super happy with how I played through my first two rounds," Fritz told reporters. "I thought today I played really well. Hopefully I can play like that again in the third round."

Fritz, the top-ranked American man, needed just 82 minutes to sweep No. 150 Cristian Garin of Chile. Fritz is looking to advance to his third-consecutive Grand Slam quarterfinal, a run that included Wimbledon 2024 and a 2024 U.S. Open finals appearance. He also was a quarterfinalist at the 2024 Australian Open.

He edged Garin 8-2 in aces and 24-9 in winners in the 6-2, 6-1, 6-0 victory. He converted 7 of 9 break point opportunities, while his foe never earned chance for a break point .

Fritz will meet No. 41 Gael Monfils of France in the third round. The winner of the Fritz-Monfils will face Shelton (No. 20) or No. 15 Lorenzo Musetti of Italy in the fourth round.

"It's going to be a fun match," Fritz said of his meeting with Monfils.

Shelton advanced with a 6-3, 6-3, 6-7(4), 6-4 win over No 182 Pablo Carreno Busta of Spain. He totaled 17 aces, compared to his foe's three. He also held a 43-22 edge in winners and converted 4 of 5 break points. Carreno Busta failed to convert six break point chances.

Tiafoe exited via upset Thursday in Melbourne. The two-time U.S. Open semifinalist held a 19-14 advantage in aces and totaled 44 unforced errors, compared to 64 for second-round foe Fabian Marozsan (No. 59) of Hungary.

Marozsan totaled 63 winners, compared to Tiafoe's 48, in the 6-7(3), 6-4, 3-6, 6-1, 6-1 win. He also converted 6 of 17 break points in the 3-hour, 17-minute match. Tiafoe converted just 3 of 20 break points. He went 0 for 10 on break points in the fourth set.

No. 42 Alex Michelsen and No. 46 Marcos Giron were the other American men to advance on Day 5 of the first Grand Slam of the tennis season.

No. 1 Jannik Sinner of Italy, No. 8 Alex de Minaur of Australia, No. 13 Holger Rune of Denmark and No. 19 Karen Khachanov of Russia also won their second-round matches.

Sinner will meet Giron in the third round. The winner will face Rune or No. 51 Miomir Kecmanovic of Serbia in the fourth round. Michelsen will see Khachanov in the third round.

The winner of the Fritz-Monfils match will battle Shelton or Musetti in the fourth round.

On the women's side, Navarro was the top American to win a second-round match Thursday at Melbourne Park. She broke No. 108 Wang Xiyu of China seven times in the 6-3, 3-6, 6-4 victory at Margaret Court Arena. She also converted 21 unforced errors, compared to Wang's 39.

Navarro, a 2024 U.S. Open semifinalist, will play No. 39 Ons Jabeur of Tunisia -- a former world No. 2 -- in the third round.

Collins beat No. 195 Destanee Aiava of Australia 7-6(4), 4-6, 6-2 in her second round match. She edged Aiava 6-5 in aces and 45-25 in winners. She converted 4 of 13 break points in the 2-hour, 25-minute meeting.

Collins, a 2022 Australian Open finalist, will face fellow American Madison Keys in the third round. Keys (No. 14), a two-time semifinalist, beat No. 125 Elena-Gabriela Rusa of Romania 7-6(1), 2-6, 7-5 in a 2-hour, 30-minute match.

No. 2 Iga Swiatek of Poland, No. 4 Jasmine Paolini of Italy, No. 7 Elena Rybakina of Kazakhstan, No. 10 Daria Kasatkina of Russia and No. 17 Beatriz Haddad Maia of Brazil were the other top women's players to win second-round matches.

No. 61 Emma Raducanu of Great Britain advanced with a straight-sets triumph over No. 35 Amanda Anisimova of the United States. Raducanu will meet Swiatek in the third round. The winner of the All-American Keys-Collins matchup will face Rybakina or No. 33 Dayana Yastremska of Ukraine in the fourth round.

No. 1 Aryna Sabalenka of Belarus, Americans Coco Gauff (No. 3) and Jessica Pegula (No. 6), No. 12 Paula Badosa of Spain, No. 13 Diana Schnaider of Russia, No. 15 Mirra Andreeva of Russia and No. 51 Naomi Osaka of Japan are expected to be the top women in action Friday.

No. 2 Alexander Zverev of Germany, No. 3 Carlos Alcaraz of Spain, No. 7 Novak Djokovic of Serbia and No. 12 Tommy Paul of the United States will be among the top men's players in third-round matches on Day 6.

Third-round coverage of Friday's matches will start Thursday in the United States, due to a major time difference in Melbourne. That coverage will begin at 7 p.m. EST on ESPN+ and 9 p.m. on ESPN2.