Two-time U.S. Open champion Naomi Osaka exited the tournament in the fourth round Monday with a 6-1, 6-4 loss to No. 2 seed Elena Rybakina of Kazakhstan.Japan's former world No. 1 gave up an early break on her second service game and from there could not gain an upper hand over the in-form Rybakina, who wrapped up the contest in 66 minutes.The 13th-seeded Osaka was "sad that I couldn't do what I set out to do" but sounded a positive note about the loss."I think I am happy that I'm taking losses differently. I'm trying to learn from them a lot more," Osaka said. "I had an opportunity to play…READ FULL ARTICLE