The final shot found the net.
Cutting a troubled figure on court, a world away from the feisty player who last season battled her way to two grand slam titles, Kerber lacked the pace and power to trouble a fellow left-hander.
The Czech said she was lucky to be alive after an incident which could have at the least ended her tennis career, but she will be back on the big stage against Julia Boserup in the first round at Roland Garros. When Boserup threatened to pull back from 3-0 to 3-2 in the opening set, Kvitova roared and pumped her fist when she saved a break point.
"I'm really happy for her and I'm glad to see all of the players giving her a warm welcome back because she deserves it and she's such a great champion and a truly awesome person off the court that she deserves that and more", said Rio Olympic gold medalist Monica Puig.
"I think it doesn't really matter how I played, but I won", Kvitova said. Everyone who helped me through the hard time. "So I'm happy that I can play", Kvitova said.
Kvitova dropped her racquet and held her head in her hands, her eyes filling with tears while her support team, wearing T-shirts marked "Courage, Belief, Pojd (Come on! in Czech)", celebrated wildly.
Asked about her hand condition, Kvitova said: 'It's still a little bit tricky sometimes. So every time I touched a ball, I felt it.
"I didn't sleep well the days after, but I wasn't really staying alone", she said.
The 15-year-old from New Jersey appeared to be on course for victory when she went 4-2 up in the second set but Nara fought back.
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Though no one immediately claimed responsibility for the attack, it had all the hallmarks of Egypt's Islamic State affiliate. And one by one, the gunmen, who had lain in wait for the convoy to appear, shot them dead, killing 29 people.
"Then when the things were even better, I was, like, "Wow, the French Open is one month, it will be great to play there".
Kvitova took the first point with a forehand victor and swiftly moved into a 3-0 lead.
The left-hander denied two break points extending her lead to 4-1.
The second set unfolded in nearly a similar fashion as the first, with Boserup losing her opening service game in the first service game of the set.
When play resumed, Kvitova continued to hit with confidence and depth.
"I did surprise myself, I have to say", Kvitova told Tennis Channel's Jon Wertheim afterward.
"I'm happy that when I'm playing I don't have pain in my hand". I'm glad the serve was there. The forehand was there.
"Yesterday I was thinking how everything will be, and I couldn't really imagine how that's going to be. It gives me some confidence and happiness inside". I did miss definitely on the court, I did miss the fight. I maybe thought that I would cry when I step on the court, but I didn't today, which actually I was happy, because normally I can control my emotion on the court, so I'm happy that I kind of did it, as well, this time.
"I was emotional in the end".