Stosur was hoping to avoid some dubious stats going into the match - she had never lost six matches in a row in her career, and she hadn't been blanked in her treasured Australian summer since all the way back in 2002, something that could have happened given she lost first round in her two lead-up events this year. And as if that weren't enough, she had lost to Chang in their only previous meeting.
But the No.9-seeded Stosur held her nerve, breaking serve with Chang serving for the first set at 6-5 and then taking control from there, eventually scrapping her way to a straight set victory, 76(3) 63.
"I desperately wanted to win out there today," Stosur said. "I didn't necessarily feel it more than first rounds in other Grand Slams, but I feel relieved and it's nice to finally get through that first round. From here, hopefully I can loosen up a little bit and keep playing better and better this tournament."
Stosur thought her numbers - 17 winners to 33 unforced errors - could be much better. "I still think there is a load of room for improvement at the moment, but it's just the start of the tournament. Hopefully each match I can get a little better. The next round is going to be very tough, so we'll see how it goes.
"I think for sure I can play better here. That's obviously what I'm trying to do this year. I'm hopeful I can turn it around. Sometimes things in tennis can change very quickly. It's a matter of keeping at it, keeping on practicing, and just doing whatever you can to try and get those good results."
And on her opponent, who went into the match with a 3-2 record against Top 10 players? "She hit some unbelievable shots where it skimmed this far over the net and hit the corners - that was one thing I knew going into the match, that if I get a hit on the ball I have to play aggressive and move forward. But even if that didn't work, just try and hang in there, because she tended to hit three or maybe four good ones and then another winner or an error. She came up with the goods when it counted though."