Kristina Mladenovic took to Instagram on Monday afternoon to announce that Sascha Bajin - former coach to World No.1 Naomi Osaka - has officially joined her coaching team.

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"Welcome to the team, coach!" the bilingual Mladenovic wrote in English and French.

Ironically, Mladenovic defeated Osaka at the Dubai Duty Free Tennis Championships back in February. Not only was it the French star's first win over a reigning World No.1, but it would also be Osaka first match without Bajin; the two announced their split shortly after the Australian Open, where the Japanese youngster had won her second straight major title.

"If she made that decision, it means that she thought was good for her," Mladenovic said in Dubai. "It's true that I think the tennis planet was surprised about this split."

Osaka avenged the loss at the BNP Paribas Open in Indian Wells, and social media sleuths soon noted that Mladenovic and Bajin, who has also worked as a hitting partner to 23-time Grand Slam champion Serena Williams and as a coach to Caroline Wozniacki, had followed one another on Instagram, and that the latter - ostensibly without a student - was heading to the Miami Open.

Mladenovic confirmed the partnership on an unofficial basis at the Hard Rock Stadium, calling Bajin a family friend who was acting as a coaching consultant for the time being.

A former World No.10, the 25-year-old made her singles breakthrough during the 2017 clay court season, reaching back-to-back finals at the Porsche Tennis Grand Prix and Mutua Madrid Open before stunning defending Roland Garros champion Garbiñe Muguruza en route to the quarterfinals in Paris. During that time, she coached herself - with some assistance from her mother and brother.

Since then, Mladenovic has continued to excel in doubles, winning the 2018 Australian Open and BNP Paribas WTA Finals Singapore presented by SC Global alongside childhood friend Timea Babos.