Coco Gauff's reign as No. 1 U.S. tennis star in danger

World No. 3 Coco Gauff has been the top-ranked tennis player from the United States — male or female — for nearly two years. 

All that could change on Saturday when No. 4 Jessica Pegula clashes against No. 1 Aryna Sabalenka in the final of the Miami Open. A win would allow Pegula to surpass Gauff in the WTA rankings and crown her as the new U.S. No. 1 in the tennis world.

Pegula pulled off an impressive semifinal victory over Alex Eala on Thursday, winning in three sets after dropping a first-set tiebreaker to the Filipino breakout star. The win meant she exercised her Miami Open demons after previous semi-final defeats in 2022 and 2023 and a quarterfinal loss to Anastasia Potapova a year ago. 

The 31-year-old American has been on a stellar run recently. After reaching the 2024 U.S. Open final, her first taste of a major final, she followed it up with a finals appearance in Adelaide and a WTA250 title in Austin, Texas. Entering the Miami Open, she had 5,361 WTA points, trailing Gauff (6,063) and leading Madison Keys (5,0004) in a three-way battle for the U.S. No. 1. 

With Gauff and Keys suffering early exits and Pegula reaching the final, the latter is at 5,796 points in the WTA Live Rankings. A win over Sabalenka would give her 6,146 points, enough to surpass Gauff.

A bad sign for U.S. tennis?

Pegula's rise would be a feel-good story for U.S. tennis, but it would be equally a poor reflection of the country's younger stars. At the Australian Open, too, fans celebrated journeywoman Keys finally winning a major but lamented the early exits of Gauff, 21, Emma Navarro, 23, and Ashlyn Krueger, 20, from the slam. 

There's no other way to slice it, but losing the U.S. No. 1 status would be a devastating blow for Gauff. The 21-year-old has failed to advance past the quarterfinals at any event this season, suffering fourth-round exits at Indian Wells and Miami and second-round losses at Dubai and Qatar. Her 2024 was also a letdown, leading to her firing her coaching staff, changing her service stance and tinkering with other aspects of her game. Gauff has become increasingly vulnerable and doesn't exude the dominant energy she did en route to her 2023 U.S. Open win.

Amid Gauff's subpar run, Rennae Stubbs, Serena Williams' former coach, recently sounded the alarm bells. Stubbs believes Gauff may lack the mental capacity to endure tough three-set battles and that "her technique fails under pressure." 

Gauff will next be seen in action at next week's Charleston Open.