After counting down the Top 5 WTA tournament matches and biggest WTA upsets of 2018, our year-end review moves to the best Grand Slam clashes of the season. Coming in at No.2 is Naomi Osaka's lone three-set match of the US Open: a thrilling fourth-round encounter against fellow rising star Aryna Sabalenka.
WHAT HAPPENED: If there's one thing that the 2018 WTA season proved, it's that the next generation is now.
That statement couldn't have been more true at the US Open, as two 20 year olds, and two of the biggest rising stars in women's tennis, squared off to start the second week.
In a highly-touted fourth round match that lived up to its billing, eventual champion Naomi Osaka ended the eight-match winning streak of Aryna Sabalenka in three sets, 6-2, 3-6, 6-4.
Read the match report: Osaka outlasts Sabalenka in US Open fourth round thriller
The crowd which gathered inside the new Louis Armstrong Stadium in Flushing Meadows might have had a general idea of what to expect when they sat down to watch the No.20 and No.26 seeds face off for the first time on Labor Day.
In one corner stood Osaka, the champion on another big stage at the BNP Paribas Open in Indian Wells, and in the other stood a red-hot Sabalenka, who was one of the stories of the summer and had come off her own first career title in New Haven prior to the year's final major.
After a near-flawless first set from the Japanese No.1, Sabalenka hit back in a big way in the second set, setting the stage for a winner-take-all decider.
Though Osaka eventually proved to be the player with more chances in the final set, the Belarusian came up with the first break of serve in the third game as she too sought a spot in her first Grand Slam quarterfinal.
After the Japanese player hit back immediately to level the action, Sabalenka did well to navigate serving troubles to hold from 0-40 for 3-3, and then from 0-30 for 4-4, as Osaka grew increasingly frustrated with her missed opportunities.
Ultimately, though, the third time was the charm for the No.20 seed, as a marathon final game - with chances for each player to win it - finally went her way on her fourth match point.
WHAT THEY SAID: Visibly emotional after over two hours of play, the victory was the first step in Osaka's personal road to history this summer, as she reached the last eight at a major for the first time.
"Every time I play a Grand Slam, people ask me am I going to go farther than the third round," she said. "Then in Australia I went to the fourth round, then people were like, 'Are you going to go farther than that or is that where you're going to stop?'
"I've always dreamed of playing here and going to the quarterfinals and further. So I'm just glad I could do one of my goals."
Osaka proved candid in her analysis of the victory, knowing that for all the opportunities that Sabalenka might provide her, the Belarusian's big-hitting could have just as easily wiped those chances away.
"I felt like I had a lot of chances to break in the third set, then she would serve these really amazing serves," said Osaka. "Like a part of me knew it was coming, but at the same time I was always very unprepared. I'm just real glad I was able to win in the end."
"I knew she hits really hard, and she has a good serve. She would attack my second serve. That's basically all I thought about. I was just trying to weather the storm. If I had chances, try to do something with the ball. Other than that, I tried to play as consistent as I can."
WHAT IT MEANT: Osaka would not be stopped en route to her first major title in New York, as Sabalenka managed to be the only player to take a set from the eventual champion in seven matches.
As she joined the ATP's Kei Nishikori in the last eight, the 2018 US Open marked the first time that a Japanese woman and man made the quarterfinals of a major since 1995.
Osaka also became the first female Japanese Grand Slam quarterfinalist since Shinobu Asagoe reached the last eight at the US Open in 2004.
"Seeing Kei do really well in Wimbledon, that really inspired me. I always thought if I can keep up with him, that would be really cool," Osaka added.
"I'm glad I was able to be a part of something like that today."
After winning one of our best Grand Slam matches of the year, Osaka later went on to claim one of our Top 5 upsets of the year in a stunning victory over Serena Williams in the championship.