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Unheralded Portuguese Nuno Borges has pulled off the biggest win of his career by knocking 13th seed Grigor Dimitrov out of the Australian Open in a third-round boilover.
The 26-year-old arrived at Melbourne Park having never made it past the second round of a major.
But the world No.69's 6-7 (3-7) 6-4 6-2 7-6 (8-6) upset of the Bulgarian on Saturday on Kia Arena moves him through to the last 16.
Borges becomes the first Portuguese man to progress to the fourth round of an Australian Open and just the second player from his country to reach the second week of a grand slam.
"I'm still processing. I still can't believe it," said Borges, who spent years playing college tennis because he wasn't mentally ready to turn professional.
"My reaction at the end was very honest, I wasn't ready to win this match when it started.
![Portugal's Nuno Borges](https://syndicates.s3.amazonaws.com/aap/assets/20240120210148/dd9cae89-06db-4850-906b-d5b344b1949f.jpg)
"It's big for Portugal. I'm proud to be Portuguese and be here competing in one of the biggest tournaments in the world.
"I hope I showed the younger kids it is possible, with a little bit of luck, working hard it is possible to achieve just living in the moment."
It was his second straight defeat of a seeded opponent after beating world No.24 Alejandro Davidovich Fokina in the second round.
Borges next faces third seed Daniil Medvedev as the resurgent Russian seeks to avenge his brutal loss in the 2022 Australian Open final to Rafael Nadal.
Medvedev admitted after his 6-3 6-4 6-3 win over Felix Auger Aliassime that he knew little about his fourth-round opponent.
"I saw the first set today, he (Borges) was playing well," the Russian said.
"I didn't know him before, but he was playing well, and to beat Grigor, who was on fire lately, is a big achievement."
Win or lose against Medvedev, Borges is guaranteed to enter the world's top 50 players for the first time at the end of the Open.
"I haven't had really too many chances to compete against most of the top 10 or top 20 guys," he said.
"I'm expecting a really tough match. I'm just going to enjoy (this win first)."