British number one Cameron Norrie booked his place in the last 16 of the Miami Open with a 6-3 7-5 win over Hugo Gaston.
Norrie broke his French opponent once on his way to taking the first set but had to battle in the second.
Gaston saved five match points as he held serve and then broke Norrie when on the brink of defeat.
But Norrie, 26, broke back instantly, to win in the 12th game of the second set with his eighth match point.
The Briton, who will make his maiden appearance in the fourth round of the tournament, is on course to break into the top 10 for the first time next week.
He will next face world number eight Casper Ruud, who has beaten Norrie in both their previous meetings.
Norway’s Ruud beat Alexander Bublik 6-3 6-2 in less than an hour.
Speaking to Amazon Prime, Norrie said: “It was one of those days where it was tough to close it out – I was a little bit stressed there. I managed to sneak through. I just got a little bit tentative and lost my feet and wasn’t moving enough.
“I was really happy with how I responded to getting broken, he’s a tricky guy. You feel like you need to be really aggressive otherwise he’s going to throw in a drop-shot at any moment. I think that’s something I need to work on.”
Czech teenager goes through
Linda Fruhvirtova became the youngest player to reach the last 16 of the Miami Open since 2004 when former world number one Victoria Azarenkaretired from their third-round match.
The 16-year-old Czech player arrived in Florida as the world number 279, but she dominated the 32-year-old two-time Australian Open winner, racing into a 6-2 3-0 lead before the tie was ended.
This was Azarenka’s seventh mid-tournament retirement or withdrawal in the past 14 months.
Fruhvirtova is playing in her first major WTA event and already had a big win under her belt after beating Belgian 24th seed Elise Mertens in the previous round.
She will now take on Spain’s Paula Badosa, who looked impressive as she beat Kazakhstan’s Yulia Putintseva 6-3 6-2, while American Coco Gauff overcame China’s Zhang Shuai 7-6 7-5.
New world number one Iga Swiatek of Poland also continued her dominant form with a 6-0 6-3 win over American Madison Brengle.
Elsewhere, Australian Nick Kyrgios cruised past Italian Fabio Fognini 6-2 6-4 as he dropped just five first-serve points.
German second seed Alexander Zverev also advanced with a 6-2 6-2 win over America’s Mackenzie McDonald.