Govortsova was playing Stosur for the first time and definitely learned how to do it really well on the job, winning the first four games of the match and eventually building a 62 51 lead in front of a stunned crowd. Stosur made a late surge, winning three games in a row to catch up to 5-4 in the second set, and she even fought off two match points, but Govortsova ended up shutting the door, 62 64.
"I think I played really well today," Govortsova said. "I had never played Sam, that was the first time, and I think it helped that I had the extra match yesterday and I don't think she played since Wimbledon. Also I played World TeamTennis last week, like four matches, which was a really great warm-up.
"At the end she had nothing to lose, so she started going for her shots and making more, and I got a little bit nervous - it was the same kind of situation as the French Open, where I had two match points against Marion Bartoli and lost, and then she went on to win Wimbledon a few weeks later.
"But I served pretty well in the last game and it helped me close out the match tonight."
Govortsova's win over the World No.13 wasn't her first Top 20 win - she now has nine to her name.
"I beat Agnieszka, I beat Bartoli before, Hantuchova when she was Top 10," Govortsova recalled. "So that's not my first big win over a top player, but it's still a pretty big victory for me, obviously."
Stosur, who was playing her first match of the summer hardcourts, was understandably disappointed.
"It was probably a few different things," Stosur said afterwards. "I didn't get off to the greatest start, losing my serve the way I did at the start, and she was playing quite well. But I wasn't able to combat that with any aggressive play of my own to not let her continue doing what she was able to do.
"The match did start to slowly kind of turn around from that 5-1 mark, when I won those three games and had a break point to go 5-all, but I obviously needed to win that last game. It's too bad."
The second night match went much more according to plan, as No.7 seed Urszula Radwanska defeated Christina McHale, 61 63. Radwanska looked headed for a much simpler victory, racing out to a 61 30 lead and points for 61 40, but she had to grind out several of the last few games to end it.
"The score actually shows that it was easy, but it wasn't," Radwanska said. "Christina is a great player, a great fighter, so she was fighting until the end, and I couldn't close the match. It was a bit shaky in the end, but the first match is always tough and I only came here a few days ago and it's always tough to change time zones. But I'm happy I played well out there tonight and that I won the match."