Indonesian qualifier Janice Tjen scored an early upset at the US Open on Sunday, ousting Russian 24th seed Veronika Kudermetova in three sets to advance to the second round.
Tjen - who is the first Indonesian to play in the singles main draw of a tennis Grand Slam since Angelique Widjaja at the 2004 US Open - showed superb poise to prevail 6-4, 4-6, 6-4.
The 23-year-old Jakarta-born right-hander took control in the first set, breaking Kudermetova twice before serving out at 6-4.
While Kudermetova hit back to level in the second set, Tjen was soon back on the front foot in the decider.
She grabbed a break in the opening game and preserved that advantage before confidently holding to love to clinch victory.
Tjen, ranked 149th in the world, will face Britain's Emma Raducanu in the second round.