Karolina Muchova edged past 17-year-old Canadian sensation Victoria Mboko 7-5, 7-6(5) to claim her first Miami Open semi-final berth.

The 29-year-old Czech veteran relied on composure under pressure, surviving a critical 0-30 deficit in the first set before winning four straight points to break Mboko’s serve and seize the opener.

The second set went to a tiebreak, where Muchova seized control with an early mini-break and held her nerve to close out the 1-hour, 47-minute clash.

"It was one point at the end," Muchova said. "I'm just grateful I won it."

The win extends Muchova’s stellar 2026 campaign-she’s reached the fourth round or better in all five tournaments this year, including her Doha title in February.

She will face either Coco Gauff or Belinda Bencic in Thursday’s semi-final.