World No.1 Naomi Osaka has ended her successful partnership with coach Sascha Bajin. The 21-year-old announced the news on Monday on Twitter.

"Hey everyone, I will no longer be working together with Sascha," Osaka wrote. "I thank him for his work and wish him all the best in the future."

Read more: The 2019 Coaching Carousel

The news comes just two weeks since Osaka's successful run to her second straight major title at the Australian Open, which launched her to World No.1. 

Bajin responded to the tweet. "Thank you Naomi. I wish you nothing but the best as well. What a ride that was. Thank you for letting me be part of this."

No other statements have been issued. 

Osaka hired Bajin during the 2017 off-season and the pair experienced near-immediate success. Osaka would go on to win her first WTA title at the BNP Paribas Open last March and solidified her status at the top of the game with her inspired run to her first major title at the US Open last fall, qualifying for her first BNP Paribas WTA Finals Singapore presented by SC Global.

READ: How Naomi Osaka's rapid rise to No.1 compares to the game's greats

Bajin was awarded the first WTA Coach of the Year award during the off-season. Prior to working with Osaka, Bajin served as the primary hitting partner for Serena Williams and a hitting partner/consultant for Caroline Wozniacki, Sloane Stephens, and Victoria Azarenka.

Osaka's next scheduled event is the Dubai Duty Free Tennis Championships, a Premier 5 event, which begins next week. 

Read more: 10 steps to the top of the world for Osaka