Hsieh, ranked 109th in the WTA Rankings, saved four break points while serving for the match at 5-4 in the third set before sealing the victory over the eighth-ranked Konta on the second match point.
"She said "oh I have a friend in Paris he can take you out for fun" and then we just go out to eat, with my team not just me, and then things work".
- The match was del Potro's first at Roland Garros since 2012, when he lost in the quarter-final to Roger Federer.
Australian Nick Kyrgios shrugged off injury concerns and kept his emotions in check to outclass Germany's Philipp Kohlschreiber 6-3, 7-6 (7/4), 6-3 yesterday and book his spot in the second round.
To try and allay her nervousness, Hsieh joked with her coach that she was too anxious to play.
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Rouhani also said that he will fulfil all the promises he made to people in his campaigns. The country may, for example, buy less weapons and enhance trade with other players.
Svitolina converted all three break points and hit 25 winners to prevail 6-4, 6-3 over Yaroslava Shvedova, a two-time quarterfinalist in Paris.
"I was very happy with the way I handled the pressure", she said. "Every time I tried to run as fast as I can and get the ball back", admitted Hsieh, who posts only her second victory in seven trips to Roland Garros.
A mini-break in the tie break was enough to hand him the second set as Kohlschreiber struggled with the Australians whipped groundstrokes and repeated audacious dropshots.
The 29th seed, whose career has been plagued by injury, confirmed his participation in this year's French Open only last Friday after suffering shoulder and back problems.
Del Potro, who reached the French Open semifinals in 2009, moved across court six with no apparent signs of discomfort, sending down 13 aces in outclassing qualifier Pella in just under two hours.
- Pironkova, who reached the quarter-finals at Roland Garros previous year, beat German Mona Barthel 6-0 6-4. I do feel I'm a better player at the end of these last few weeks on the surface than I was at the beginning and that is the most I can ask of myself: "to keep improving".
But Hsieh fought back and Konta had to save five break points before her opponent eventually prevailed in the second-set tiebreaker.