Ashleigh Barty had gone more than 14 months without facing a Top 10 player. To be fair, it was more a factor of her staying home during the pandemic and some quirky math. She beat Garbine Muguruza when she was ranked No.15 in the Yarra Valley Classic final and No.16 a year ago in Qatar. Petra Kvitova was No. 11 when she beat Barty in the Qatar semifinal.

Still, you had to wonder.

But Tuesday after Barty defeated No. 7 seed Aryna Sabalenka to reach the Miami Open semifinals in a rousing 6-4, 6-7 (5), 6-3 match, wonder no more.

“It was a brilliant match today,” Barty said afterward in her on-court interview. “It was certainly the best level I’ve played for a long time and especially over a sustained period.”

Barty has now won 10 straight matches in Miami, going back to the 2019 title that makes her the defending champion. She’s 12-2 for 2021.

If Barty reaches the final here, she’ll retain the No.1 ranking, ahead of Osaka. If she doesn’t, Osaka can overtake her only by winning the title.

Heading into this widely anticipated match, Barty and Sabalenka’s resumes – outside of Barty’s major success – were remarkably similar.

Sabalenka held a 3-2 head-to-head advantage, and her win over Barty two years ago in Wuhan was the first and only against a world No.1. Both were playing in their 28th WTA quarterfinal and both hold nine singles titles. Barty was the 2019 French Open champion, but Sabalenka won the Australian Open doubles title earlier this year, teaming with Elise Mertens.

It’s easy to forget that Sabalenka, at 22, is two years younger.

Serving at 2-3 in the first set, Barty was down triple-break point but won the game’s last five points. Sabalenka, serving at 4-all, granted her first break point of the match – and promptly double-faulted twice. The last two balls missed by about a foot each.

Sabalenka rallied to win six of the last seven points in the second-set tiebreaker. During the sixth game of the third set, though, she seemed to be visited by an upper body injury. Clearly distracted, Sabalenka lost the last three games of the match and 12 of 13 points.

“Aryna really made me bring out my best stuff today,” Barty said. “She’s an exceptional competitor and someone who I respect so much on the court. She’s just got the game to make you really uncomfortable so it was about trying to hang in there as best I could today.”

2021 Miami Highlights: Barty powers into SFs with Sabalenka win

Despite a series of tight matches through the first week, five of the top eight seeded players reached the quarterfinals: No.1 Barty, No.2 Osaka, No.5 Elina Svitolina, No.7 Sabalenka and No. 8 Bianca Andreescu.

And yet, it’s a testament to the depth in the game that Barty was pushed to match point in her first match, against Kristina Kucova, while Sabalenka faced two match points in her first outing, against Tsvetana Pironkova.

Barty said after her fourth-round win over Victoria Azarenka that she still hadn’t played her best tennis. Now she’s starting to settle in, and on Tuesday looked a lot like a World No.1.

“You can’t see me, but there’s a massive smile behind my mask,” Barty said on the court. “It’s always nice to come back somewhere we’re you’ve had good memories. This was one of my favorite weeks in my career a couple of years ago. It’s where I broke into the top 10 for the first time.

“Yeah, it’s a tournament that I just love coming back to.”