This time there was no such controversy surrounding Naomi Osaka's Grand Slam victory.

Osaka took advantage of her second chance in the third set to defeat Petra Kvitova 7-6 (2), 5-7, 6-4 on Saturday, win the Australian Open and become a back-to-back Slam champion.

"I felt like I didn't want to have any regrets," Osaka said. "I think if I didn't regroup after the second set, then I would have looked back on this match and probably cried or something."

Her US Open victory last year was largely overshadowed by the tense standoff between Serena Williams and chair umpire Carlos Ramos. The umpire's decision to level point and game penalties against Williams became the focus in the aftermath of that match.

Saturday's match stayed between the lines, as Osaka closed out the victory on her serve after being unable to do so on her first opportunity in the second set.

The title win also means Osaka will become the first tennis player from Japan to reach No. 1 in the rankings. The 21-year-old will also be the youngest No. 1 in nearly a decade; Caroline Wozniacki was 20 when she first ascended to that spot in 2010.

"Women's tennis is very open. You really never know who going to be there. But definitely she's playing great game," Kvitova said. "She's really big player, as she showed in the results, winning the US Open and Australian Open, it's an amazing achievement."

After taking control of the match in the second set by breaking Kvitova's serve twice in a row, Osaka stumbled while trying to finish the sweep. She was unable to take advantage of three championship points on Kvitova's serve at 5-3 and then was broken twice to send the match to a decisive set.

Osaka was yelling at herself. She slammed a ball off the court. She tugged at her pink visor's brim. She headed to the locker room after the second set with a towel draped over her head.

At that point, Kvitova would say later, she figured it was going to keep going her way.

"In the end," she said, "it wasn't."

Hard as it must have been, Osaka regrouped. She also got her powerful shots going again. After Kvitova double-faulted to offer up a break point at 1-all, Osaka converted it with a crosscourt backhand winner. There was still more work to be done and some additional drama when it began raining at the changeover right before Osaka tried to serve for the match at 5-4 in the third set.

This time, Osaka would not falter. She would not let this lead disappear.

"I knew that Petra couldn't keep it up for that long if Naomi could just manage those emotions," said Osaka's coach, Sascha Bajin, "and she did that beautifully."

Australian Open champion Naomi Osaka will become the first tennis player from Japan to reach No. 1 in the rankings. Cameron Spencer/Getty Images

In the first set, Osaka had to save two break points in the fifth game and three in the seventh, when she came back from 0-40, to hold. From then on, she applied most of the pressure on Kvitova, a two-time Wimbledon winner.

No. 8 Kvitova saved two set points while serving to stay in the set and held with a backhand crosscourt winner to force the tiebreaker.

But Osaka dominated the tiebreaker, earning another four set points when Kvitova netted a backhand and converting the first of those on another error from the Czech player.

Osaka became the first woman since Jennifer Capriati to win both of her first two Grand Slam finals. Capriati did so at the 2001 Australian and French opens.

Before the two Slam victories, Osaka had never made it past the fourth round of a major (2018 Australian Open) and was ranked 72nd a year ago. Osaka is the first woman to win two major championships in a row since Williams picked up four straight in 2014-15.

Kvitova was playing in her first Grand Slam final since winning Wimbledon in 2014 -- and the first since she was stabbed in the hand by an intruder at her home in the Czech Republic a little more than two years ago.

She needed surgery, missed more than four months to start the 2017 season, including the Australian Open, and couldn't be sure she would ever get back to the top of tennis.

"I can't really believe," Kvitova told the Rod Laver Arena crowd, "I played the final of a Grand Slam again."

Kvitova, who will now be ranked No. 2, matching her previous career best, proved to herself that she can be the player she used to be and can contend for Grand Slam championships.

"I wanted to win and have the trophy, but I think I already won two years ago," she said. "I feel great. I'm playing great tennis. I don't think that I could really imagine ... [being] kind of this player again."

On a somewhat cloudy, rather comfortable evening, with only a slight breeze and the temperature around 75 degrees, both women hit the ball as hard as can be. Exchanges were mostly at the baseline and filled with flat, powerful groundstrokes that barely cleared the net and made retrieving and replying as much about reflexes as anything.

Here's one measure of how even it was: Each finished with 33 winners.

Points were swift and blunt. Of 86 in the first set, only four lasted nine strokes or more. There was plenty of strong serving, clean hitting and good movement.

It was Osaka who was the first to get ahead, tearing through the tiebreaker by grabbing five points in a row -- four via winners -- to go up 5-1. When Kvitova sailed a backhand wide moments later, ceding a set for the first time all tournament, Osaka pumped her fist and screamed, "Come on!"

How pivotal was that moment? Kvitova had won her past 22 Grand Slam matches after winning the first set. Osaka, meanwhile, entered the day having won 59 matches anywhere after going up by a set.

When Osaka broke to lead 3-2 in the second set and then got to 5-3, the outcome seemed to be a foregone conclusion. Turned out, that wasn't the case. Not at all.

All that really matters, of course, is that Osaka righted herself in time to win.

"It didn't really take that long," she said. "I didn't have a choice."

The Associated Press contributed to this report.