Patrick Mouratoglou announced Thursday he is going to start working with former World No.1 Simona Halep.

Mouratoglou, who has famously coached Serena Williams for a decade, said he is ready to start a new chapter in his life.

“In the last 8 months, I realized how much I missed coaching,” Mouratoglou wrote on social media. “It is the passion of my life, and I still feel like I have so much to give.”

Mouratoglou noted that Halep, a two-time Grand Slam winner, went to his tennis academy ahead of Indian Wells in early March.

“At the end of the week, she asked me if I was available to coach her,” Mouratoglou said. “I have the highest respect for her, but it was out of the question at the time. A few weeks later, I had a conversation with Serena, and the door opened for me, at least short term, to work with someone else. I will keep you updated on what’s coming next soon.”

Williams, who owns 23 Grand Slam titles, one behind all-time leader Margaret Court, has not played since injuring her hamstring at Wimbledon last year. With Mouratoglou, Williams, 40, won 10 majors.

Halep has played well this season. In her second event of the year, she won a WTA 250 event in Melbourne before falling in the fourth round of the Australian Open. She was also a semifinalist in Dubai and Indian Wells.

Last September, Halep announced she and longtime coach Darren Cahill were parting ways.