Halep, a former world No. 1, showed interest in working with Mouratoglou but he couldn't accept the offer at first as he is listed as the coach of Williams. Since Williams hasn't played since Wimbledon, Mouratoglou hasn't coached in a while prompting him to fly to America and have a talk with her.
Patrick Mouratoglou revealed as new full-time coach of Simona Halep, hints at future of Serena Williams in statement
He revealed what he said to her:
"I missed it big time. Coaching is the passion of my life. It’s the job of my life. And when I went to see Serena to discuss before starting with Simona, that’s what I told her. I said, ‘Coaching is the passion of my life and it’s difficult for me not to work.’ So yes, I missed coaching big, big time. Honestly, since I’m back to coaching with Simona, I cannot be happier to coach this again. It’s an incredible satisfaction for me to do that job. It’s incredible."