Rising American Brandon Nakashima beat veteran John Isner 7-6(7) 6-3 to set up a second round meeting with Daniil Medvedev in first round action at Indian Wells on Wednesday.
Nakashima, 21, saved a set point in the first breaker and stepped up his defense in the second to see off the big-serving Isner before a crowd that included Kansas City Chiefs quarterback Patrick Mahomes and his family.
"Coming to this tournament, it's always super exciting for me," said Nakashima, who made his tour debut at Indian Wells in 2018.
"Growing up here, close by in San Diego, it's one of the tournaments where I grew up coming here as a little kid, watching all the top pros.
"So to be able to play here now against another top American on the centre court here, is a super special feeling."
He will have his work cut out for him when he faces world number six Medvedev, who has won three consecutive titles and is on a 14-match winning streak.
In other first round action, Australia's Jordan Thompson crushed Frenchman Gael Monfils 6-3 6-1 and Diego Schwartzman made quick work of fellow Argentinian Federico Coria 6-1 6-2.
Ugo Humbert will face hard hitting Canadian Denis Shapovalov after the Frenchman topped Bernabe Zapata Miralles of Spain 6-2 7-6(6).
In the women's draw, Shelby Rogers won an all-American battle with Katie Volynets 6-4 4-6 6-1.
"She definitely has a very bright future and unfortunately only one of us could win today," Rogers said.
"She's one of the nicest girls I've met on tour and I look forward to seeing her more."
Next up for Rogers is a second round meeting with seventh seeded Maria Sakkari. Rogers holds a 3-0 lead in her career meeting with the Greek.
Italy's Camila Giorgi, China's Wang Xiyu and Ukrainian Lesia Tsurenko were among the other first round winners at the Masters and WTA 1000 event in the Southern California desert.
