Following a succession of surprise results during the WTA's recent double-header in Dubai and Doha, Chang became the latest underdog to have her day, producing a rousing early evening comeback to defeat top seed Vinci, 5-7, 6-2, 6-1.
The result, though, is by no means an isolated one. In fact, Chang has made a habit of defeating Top 10 players, Vinci joining a list that also includes Dinara Safina, Marion Bartoli and Samantha Stosur.
"It's always an honor to play a Top 10 player and I really enjoyed the whole match," Chang said. "I told myself after the first set to be more patient, so I slowed everything down, kept more balls in and just played with her. The result came out well!
"She's very difficult to play because she slices and spins it, and I'm very happy I could win this match."
No.2 seed Elina Svitolina fared better rather better in her first-round outing, requiring only 47 minutes to defeat qualifier Miyu Kato.
There were mixed fortunes for Svitolina in the Middle East, as a semifinal in Dubai was followed by a surprise first-round loss to Denisa Allertova in Doha. And Svitolina took out her frustration on qualifier Kato, breaking five times, whilst giving up just seven points on her own serve, en route to a 6-1, 6-1 victory.
"I'll try and do the same thing - play the ball and not the opponent, which is the most important thing to me," Svitolina said. "I think she's playing well. She had a good win today and it's always tough to play a qualifier, because they've had a couple of matches and it's completely different conditions here than to Doha and Dubai."
A fixture inside the Top 20 for the best part of a year now, Svitolina is flying the flag for Ukrainian tennis and this summer will have the opportunity to represent her motherland on the greatest sporting stage of all.
"The Olympics is a big event. It's the first time for me so it's going to be a really different experience and it's amazing that I'm going to represent my country and play for Ukraine. It's just a great thing."
After last year's French Open, Svitolina overtook Alona Bondarenko as Ukraine's highest-ranked player of all time, a status that is a source of great pride: "It feels really great since I am the highest ever Ukrainian woman. So for me it was a big thing after Roland Garros when I became one of the highest."
Diyas caused the day's biggest upset, knocking out No.4 seed Annika Beck, 7-5, 6-3. Broady, meanwhile, fired down 17 aces to win a see-saw encounter with Klara Koukalova, 6-3, 3-6, 6-3, and Zhaoxuan fought back to defeat No.8 seed Zheng Saisai, 4-6, 6-3, 6-2.