Osaka guts out a win back-to-back Grand Slam championships (WTA Facebook)

There’s a new No. 1 in women’s tennis. Naomi Osaka grabbed the crown by defeating Petra Kvitova 7-6 (2), 5-7, 6-4 at the Australian Open in a thrilling finals match.

Osaka — who is of Haitian and Japanese descent and has dual Japanese-American citizenship — also made history as the first Japanese player to reach No. 1, pulling off back-to-back Grand Slam championships.

The 21-year-old tennis phenom showed grit and composure as she battled Kvitova in a slugfest, overcoming three lost match points and outlasting her opponent in three sets.

Osaka’s semi-finals match against Karolina Pliskova served as a good primer. The newly minted tennis star charmed the crowd as she corralled her emotions, settled her nerves, and willed herself to a 6-2, 4-6, 6-4 victory.

At the finals on Saturday, the battle-tested Osaka was ready to go the distance, coming out victorious in a two-and-a-half-hour duel against Kvitova to covet the trophy and $2.9 million in winnings.

What a difference a year makes. This time last year Osaka didn’t even rank in the top 50 of women’s tennis. She gained widespread prominence at last year’s U.S. Open, as she toppled her idol, champion Serena Williams, in straight sets 6-2, 6-4. But Osaka’s win was eclipsed by controversial calls against Williams and the media firestorm that followed.

The soft-spoken Osaka was able to bask in her win a bit more at the Australian Open, telling the cheering crowd, “Sorry, public speaking isn’t my strong side. Huge congrats to you Petra, you’re amazing, and I’m really honored to play you in a Grand Slam.” She thanked her family, team and supporters and added, “I read notes before this, but still I forgot what I am supposed to say. So, thank you.”

This time, the controversial headlines were due to off-court issues, as Japanese noodle company Nissan, one of Osaka’s sponsors, was forced to apologize for “Whitewashing” her image in an ad.

Osaka, who proudly claims her dual heritage, said that although she didn’t think the company meant to “Whitewash” her image, “I’m tan. It’s pretty obvious… I definitely think that the next time they try to portray me or something, I feel like they should talk to me about it.”

She said the flap wouldn’t deter her focus on her main priority — winning another Grand Slam. She was right. With this win, Osaka becomes the first women since Jennifer Capriati in 2001 to win her first two major titles back to back.

The next Grand Slam tournament for Osaka will be the French Open in late May.