Raducanu races into Miami Round 2; Canadian teenager Mboko upsets Osorio

In her third appearance at the Miami Open, Emma Raducanu claimed her first win, defeating 19-year-old wild card Sayaka Ishii 6-2, 6-1 in just 65 minutes.

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The former US Open champion will face No. 8 seed Emma Navarro in the second round, her first meeting with a Top 10 player since losing to Iga Swiatek in the Australian Open third round.

"It's going to be an extremely challenging match," Raducanu said in her on-court interview. "She's probably in better form, so I can go out and express myself and try and compete for every point."

In Raducanu's previous Miami appearances, the Briton fell in a pair of three-set barnburners -- to Katerina Siniakova in the 2022 second round, and to Bianca Andreescu in the 2023 first round. Against Ishii, there were no such twists and turns. The Japanese teenager, who has improved from No. 381 to her current No. 188 over the past 12 months, was contesting her third WTA main draw, having already reached the Tokyo quarterfinals on home soil last October.

Ishii showed her potential with some heavy forehands early on, but Raducanu responded with a near-flawless serving display, slamming down six aces across the match. Ishii was unable to sustain the accuracy of her early aggression, committing 24 unforced errors in total.

Mboko brings hot form to tour level in style

There was delight for another teenage wild card, Victoria Mboko, who came through an enthralling three-setter to upset Camila Osorio 7-5, 5-7, 6-3 in 2 hours and 32 minutes.

The 18-year-old Canadian has been in hot form at ITF level in 2025. Across venues in the Caribbean, Georgia, England and Portugal, she has collected five titles already, and her overall season record now stands at 28-1. Now ranked No. 162, her match with Osorio was a test of how that level would translate to WTA level against one of the tour's most renowned fighters. Mboko passed with flying colors, coming away with both her first Top 100 victory and her maiden WTA main-draw win (having lost to Rebecca Marino on her debut at Granby 2022).

Twists and turns abounded throughout the match. Superb hitting off both wings took Mboko to a 5-2 first-set lead, but she needed five set points to close it out as Osorio clung on valiantly. In the second set, it was Mboko who pegged Osorio back from an early break down -- winning the point of the match, a brilliant cat-and-mouse exchange that she ended with an emphatic smash, en route. But the Colombian held on to force a decider.

To rebound from those fluctuations in the third set was a testament to Mboko's fortitude, as was her ability to hold Osorio off in the home stretch. Mboko had a point to lead 4-1, only for the World No. 54 to deny her and level at 3-3. Osorio has pulled off plenty of great escapes in her time, and conjured a series of deft drop shots as she attempted to reel Mboko in.

But the youngster inched out to 5-3 again, and sealed a memorable victory on her first match point as an Osorio backhand went just wide. Mboko will next face a Top 20 player for the first time in her career as she takes on No. 10 seed Paula Badosa in the second round.