Tjen first Indonesian to win at Australian Open in 28 years
Unseeded Tjen stunned Canadian 22nd seed Leylah Fernandez 6-2, 7-6 (7/1) to surge into the second round in Melbourne and add to her growing list of milestones.
Tjen, who this time last year was ranked 413 but is now the world number 59, is the first Indonesian to win a match at the major since Yayuk Basuki in 1998.
"I'm very happy to be a part of history and be able to get a win here for Indonesia," said the 23-year-old.
"It was special, especially being able to do it in front of my family here and there were a lot of Indonesians...