Mikaela Shiffrin reacted to Naomi Osaka's victory in the fourth round of the US Open against Coco Gauff. Osaka asserted her dominance in the match and claimed the victory in straight sets with a score of 6-3, 6-2.The fourth-round match between the two players raised great anticipation among fans. They were going head-to-head once again at the Arthur Ashe Stadium six years after their first clash in 2019. Naomi Osaka eliminated the third seed in an hour and four minutes to advance to her first Grand Slam finals in four and a half years.About competing against Gauff in the fourth round, Naomi Osaka said:"She’s one of the best players in the world. For me, I have the most fun when I play against the best. I always see it as a challenge. And I like challenges.”Moreover, Osaka will be competing in the fifth Grand Slam quarter-final of her career on Wednesday, September 3. Her incredible performance against Coco Gauff drew many reactions from athletes all around the world. Mikaela Shiffrin, who closely follows tennis, reacted to her victory with a set of emojis and expressed her elation."🥳🥳" she tweeted.Additionally, Naomi Osaka went on to win the Grand Slam title the last four times she advanced to the quarterfinals.When Mikaela Shiffrin opened up about being impressed by Naomi OsakaMikaela Shiffrin at the STIFEL FIS World Cup Finals - Slalom - Source: GettyMikaela Shiffrin opened up about watching Osaka in an interview with VailDaily in 2019. The American skier expressed that she was really excited to witness Osaka evolve as a player and lauded her ability to stay calm during crucial moments of a match.Moreover, Shiffrin lauded Osaka's efforts to rise up the ranks in a competitive sport on a circuit that then had players like Serena Williams.“Somebody I’ve been watching lately, and I’m really excited for, is Naomi Osaka. I think that she at least seems like a really nice, down-to-earth girl, trying to do her job and coming up the ranks in a sport that has Serena Williams, the face of tennis," she said.Shiffrin expressed that it was incredible to witness Osaka compete against some of the best players in the sport with incredible grit and determination.“Watching Osaka and seeing how she handles herself competing against one of her biggest idols has been pretty cool for me to see," she added.The American tennis player will compete against Karolína Muchová in the US Open quarterfinals on September 3.