Melbourne - Tennys Sandgren sent eighth seed Matteo Berrettini packing from the Australian Open Wednesday as the American eyes another strong performance after his scandal-marred run to the 2018 quarter-finals.
Berrettini, last year's US Open semi-finalist, slumped to defeat in a five-set marathon which finished 7-6 (9/7), 6-4, 4-6, 2-6, 7-5 in 3hrs 23 mins - the highest ranked seed to fall so far.
It was a disappointing end for the Italian, who reached the US Open semi-finals and stormed up the rankings last year, reaching a new career-high 10 times.
"It was a top-10 win in a Slam so I'd say it's up there," said Sandgren. "I'm not sure where it lies in the ranking list but pretty high."
Sandgren, a devout Christian, achieved his best Grand Slam result at Melbourne Park in 2018 when he reached the last eight but it was overshadowed by controversy over his political views and links to right-wing activists.
Sandgren was forced to wipe the slate clean, deleting years of social media postings.
Among his tweets, Sandgren had appeared to back a debunked online conspiracy in 2016 which linked Hillary Clinton to a supposed child sex abuse ring at a Washington pizzeria.
He also retweeted a video from white nationalist Nicholas Fuentes.
Sandgren did not want to comment on the 2018 episode after his Berrettini win, but acknowledged the experience "had helped me with my game".
Ranked 100, he said he played better at the Slams, having made the fourth round at Wimbledon last year and the third round at the US Open.
"I had some good weeks at the Slams last year. I like these tournaments a lot where it feels like one of the few weeks where it actually feels like it means something," he said.
"You know, sometimes you get lost when you're travelling a lot and playing 30 or 35 weeks a year -- I certainly get lost out there sometimes, so I feel my game kind of comes together at these types of weeks.
"And I just feel fresher in January."
His reward for beating Berrettini is a third-round clash against fellow American Sam Querrey.
Results on day three of the Australian Open Grand Slam at Melbourne Park on Wednesday:
Men's singles
2nd round
Tennys Sandgren (USA) bt Matteo Berrettini (ITA x8) 7-6 (9/7), 6-4, 4-6, 2-6, 7-5
Sam Querrey (USA) bt Ricardas Berankis (LTU) 7-6 (7/2), 4-6, 6-4, 6-4
Guido Pella (ARG x22) bt Gregoire Barrere (FRA) 6-1, 6-4, 3-6, 6-3
Marton Fucsovics (HUN) bt Jannik Sinner (ITA) 6-4, 6-4, 6-3
Tommy Paul (USA) bt Grigor Dimitrov (BUL x18) 6-4, 7-6 (8/6), 3-6, 6-7 (3/7), 7-6 (10/3)
John Millman (AUS) bt Hubert Hurkacz (POL x31) 6-4, 7-5, 6-3
Stefanos Tsitsipas (GRE x6) bt Philipp Kohlschreiber (GER) walkover
Milos Raonic (CAN x32) bt Cristian Garin (CHI) 6-3, 6-4, 6-2
Marin Cilic (CRO) bt Benoit Paire (FRA x21) 6-2, 6-7 (6/8), 3-6, 6-1, 7-6 (10/3)
Diego Schwartzman (ARG x14) bt Alejandro Davidovich (ESP) 6-1, 6-4, 6-2
Dusan Lajovic (SRB x24) bt Marc Polmans (AUS) 6-2, 6-4, 6-3
Yoshihito Nishioka (JPN) bt Daniel Evans (GBR x30) 6-4, 6-3, 6-4
Novak Djokovic (SRB x2) bt Tatsuma Ito (JPN) 6-1, 6-4, 6-2
Roger Federer (SUI x3) bt Filip Krajinovic (CRO) 6-1, 6-4, 6-1
Fabio Fognini (ITA x12) bt Jordan Thompson (AUS) 7-6 (7/4), 6-1, 3-6, 4-6, 7-6 (10/4)
Roberto Bautista Agut (ESP x9) bt Michael Mmoh (USA) 5-7, 6-2, 6-4, 6-1
Women's singles
1st round
Sara Sorribes (ESP) bt Veronika Kudermetova (RUS) 2-6, 6-1, 6-1
Anett Kontaveit (EST x28) bt Astra Sharma (AUS) 6-0, 6-2
Iga Swiatek (POL) bt Timea Babos (HUN) 6-3, 6-2
Carla Suarez (ESP) bt Aryna Sabalenka (BLR x11) 7-6 (8/6), 7-6 (8/6)
Elise Mertens (BEL x16) bt Danka Kovinic (MNE) 6-2, 6-0
Heather Watson (GBR) bt Kristyna Pliskova (CZE) 4-6, 6-3, 6-1
Anastasia Pavlyuchenkova (RUS x30) bt Nina Stojanovic (SRB) 6-1, 7-5
Taylor Townsend (USA) bt Jessica Pegula (USA) 6-4, 7-6 (7/5)
2nd rd
Ashleigh Barty (AUS x1) bt Polona Hercog (SLO) 6-1, 6-4
Elena Rybakina (KAZ x29) bt Greet Minnen (BEL) 6-3, 6-4
Alison Riske (USA x18) bt Lin Zhu (CHN) 6-3, 6-1
Julia Goerges (GER) bt Petra Martic (CRO x13) 4-6, 6-3, 7-5
Maria Sakkari (GRE x22) bt Nao Hibino (JPN) 7-6 (7/4), 6-4
Ekaterina Alexandrova (RUS x25) bt Barbora Krejcikova (CZE) 6-1, 6-3
Petra Kvitova (CZE x7) bt Paula Badosa (ESP) 7-5, 7-5
Naomi Osaka (JPN x3) bt Saisai Zheng (CHN) 6-2, 6-4
Cori Gauff (USA) bt Sorana Cirstea (ROU) 4-6, 6-3, 7-5
Shuai Zhang (CHN) bt Caty McNally (USA) 6-2, 6-4
Sofia Kenin (USA x14) bt Ann Li (USA) 6-1, 6-3
Ons Jabeur (TUN) bt Caroline Garcia (FRA) 1-6, 6-2, 6-3
Caroline Wozniacki (DEN) bt Dayana Yastremska (UKR x23) 7-5, 7-5
Qiang Wang (CHN x27) bt Fiona Ferro (FRA) 6-1, 6-2
Serena Williams (USA x8) bt Tamara Zidansek (SLO) 6-2, 6-3
Madison Keys (USA x10) bt Arantxa Rus (NED) 7-6 (7/3), 6-2