"This has been the best two weeks of my life and I'll forever remember this," Sofia Kenin tells PEOPLE
Australian Open
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Sofia Kenin showed her dominance on the tennis court over the weekend, and now she’s reveling in her victory.

The 21-year-old American athlete took her first-ever singles Grand Slam title at the Australian Open on Saturday, becoming the youngest woman to win the tournament in over a decade.

Kenin, a player on the WTA Tour, tells PEOPLE, “This has been the best two weeks of my life and I’ll forever remember this.”

The athlete defeated Garbiñe Muguruza in three sets, (4-6, 6-2, 6-2), a match she admits to PEOPLE she was “nervous” for.

“I felt that I’m one step closer to achieving what I’ve always wanted, and it was to be a Grand Slam champion,” she recounts. “During the match there were nerves for sure but I just kept telling myself to keep fighting, don’t give up, keep believing, leave your heart out.”

Adds Kenin, “The 2-2 game in the third set when I was down 0/40 in the game, I had to play the best points to change the match around. Those points were very crucial and it really changed things for me and from there I got even more confident.”

Muguruza is a “tough player,” she notes, explaining, “I knew she was going to come out playing some really good tennis and she did. The whole match was very tough, she wasn’t giving up and we had some really long points.”

Australian Open
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After the trophy ceremony on Saturday, Kenin told the excited crowd at Rod Laver Arena: “I’m on cloud nine right now, I just can’t believe this.”

The moment, she tells PEOPLE, was “just surreal.”

“It’s a dream come true for me! I’ve worked so hard and have been through some tough times and this made me work even harder to achieve my dream,” she says. “I feel like I’m living my dream and this means everything to me!”

There will be no downtime, now, for the young champion, who is only taking a few days off before playing in the Fed Cup.

Says Kenin, “I can’t wait to be back competing there and representing my country!”