MELBOURNE, Australia — Though he is only 24, Taylor Fritz had been waiting a long time for the breakthrough he finally reached at this Australian Open.

Playing in his 22nd Grand Slam main draw, the 20th-seeded Fritz reached the fourth round of a major for the first time, defeating the 15th-seeded Roberto Bautista Agut, 6-0, 3-6, 3-6, 6-4, 6-3, on Saturday.

Fritz had reached the third round seven times previously at Grand Slam events, but he often fell short against the game’s best, losing to players like Roger Federer, Novak Djokovic and Dominic Thiem.

Fritz had also lost five of his previous six matches against Bautista Agut, who he joked in his postmatch news conference “has basically been my dad my whole professional career.” But Fritz largely dictated the play throughout the five sets with his forehand, hitting 73 total winners compared to Bautista Agut’s 35.

The win was an emotional one for Fritz, who had grown increasingly frustrated with his inability to make the round of 16 in a major draw.

“I’m a very confident person, and I put a ton of pressure on myself to be better,” Fritz said in an interview. “So it’s been tough for me to not have this fourth-round experience yet with so many opportunities and, I feel like, being the caliber of player who deserved to make at least one. But at the same time, I’ve got to look back and look at all of the matches — a lot of really tough draws.”

Fritz will play the fourth-seeded Stefanos Tsitsipas on Monday.

Fritz, who won the U.S. Open boys’ title in 2015, has long been considered a great hope for American men’s tennis, which has been without a Grand Slam tournament champion since Andy Roddick won the 2003 United States Open. Ranked 22nd, Fritz currently sits atop the American ladder, but these days it is a short ladder.

In 2010, there were no American men in the top 10 of the ATP rankings for the first time since the rankings began in 1973. In 2013, there was no American player in the top 20. Last year, for the first time, there were no Americans among the top 30 players.

“It’s really cool to be the No. 1 American — don’t get me wrong,” Fritz said. “It’s been a dream my whole life. But with the caliber that U.S. tennis fans are used to, I can’t walk around all high and mighty and proud being the No. 1 American, I feel like, if I’m not ranked a bit higher.”

Fritz, who could make his top 20 debut with his run in Melbourne, hopes to halve his ranking this year.

“I want to be top 10 this year,” Fritz said. “That’s my goal, and I’ll be really disappointed if it’s anything less than that. I feel like, since Indian Wells, I’ve been playing at that level, and it’s a question of staying healthy and keeping this level up. And if I keep doing it, I think that’s where I’m going to be. I put a lot of pressure on myself, and I’m really confident, but you have to be if you’re going to make it.”

Fritz said that believing in himself — even in the times when he was struggling — had been a critical part of his climb.

“How can you ever be good or be the best if you don’t truly — like, truly — believe that you can be?” he said. “I’m a great example of someone who wasn’t good at all when I was 15 years old. But I had this crazy false sense of confidence. Just because you believed, you put in the hard work and you make it happen.”

“All the best players in the world have believed that,” he added. “Regardless of how much they’ve let on how confident they truly are. Success can never happen if they don’t really, really believe it.”

Paul Annacone, the veteran American coach who has worked with Fritz, said that Fritz now feels “comfortable” that his usual level of tennis can be enough to compete with the game’s best.

“To me, that’s what it takes to go from one level to the next,” Annacone said. “I think his average levels have gotten way better, and I think that that’s going to help him a lot this year.”

Fritz’s profile will grow this year with or without more breakout tournaments. He is one of a handful of players being followed by camera crews this week at Melbourne Park as production begins on a new Netflix series about the professional men’s and women’s tennis tours. Fritz said he was eager to give viewers a look at himself on and off the court for the first time.

“I’m a very easygoing, relaxed guy, and I’m very confident,” he said. “I believe in myself a lot, and I’m a really tough, really hard worker. And I hope that shows, and I hope that sometimes my confidence doesn’t come off as cockiness.”

Christopher Clarey contributed reporting.