Key Points
Fonseca battled illness and cramps during dramatic Miami Open match
Teenager won in two hours and 23 minutes
Struck 43 winners against Learner Tien
Advanced to face Ugo Humbert next
In the youngest main-draw match in Miami since 2016, when Alexander Zverev beat Michael Mmoh in a battle of 18-year-olds, Fonseca struck 43 winners to win the match in two-hour, 23-minute.
"I always try to be aggressive with my forehand. When I was younger, I went to my forehand when the important points came and it'd go directly to the fence. Now I'm working a little bit more to be aggressive and solid at the same time. In the important points, I go with my forehand where I have confidence. Very happy and proud of myself the way I put in the hard work on court," Fonseca said.
Leading 3-2 in the decider with a break advantage, Fonseca stood up from the changeover and unexpectedly called the doctor, telling chair umpire Mohamed Lahyani that he felt dizzy and needed to vomit. Fonseca took pills from the doctor and following a six-minute break, he continued the match without any obvious signs of illness, ATP reports.
The late drama continued as Fonseca appeared to suffer from a small cramp just two points from the win. But the teenager wasted no time as he wrapped up the win.
Fonseca will next meet 19th seed Ugo Humbert, who last month won his seventh tour-level crown in Marseille.
In other action, Jakub Mensik overcame Roberto Bautista Agut 6-4, 3-6, 6-1 after hammering 23 aces and winning 84 per cent of his first-serve points.
Italians Lorenzo Sonego, Matteo Arnaldi and Luciano Darderi all advanced. Sonego, 29, ousted Mariano Navone 7-5, 7-5 to set a second-round clash with third seed Taylor Fritz. Arnaldi overcame Wu Yibing 7-6(3), 4-6, 6-3 while Darderi raced past Pedro Martinez 6-4, 6-1.
