NEW YORK, NY, USA - Much has been made of the positive influence Patrick Mouratoglou has had on Serena Williams' game, and with good reason.
Since they joined forces 15 months ago, Williams has won three majors, Olympic gold and re-established herself as the woman to beat on tour. However, as good a job as Mouratoglou has done, he inherited some rather special raw material.
Williams is the poster girl for 21st century tennis, her perfect blend of athleticism, bludgeoning groundstrokes and fiery competitiveness setting the standard against which all of her peers are measured.
The man who laid the foundations for this all-conquering game was her father Richard Williams, who, despite having no professional experience, took Serena and her sister Venus from the pockmarked municipal courts of Compton to Grand Slam glory.
Yet, despite the sisters' numerous successes, the tennis community has been somewhat reluctant to heap praise on Richard, something that continues to perplex his younger daughter.
"I think that everyone who may have said my dad wasn't a good coach in the past obviously needs to realize that the results between myself and Venus speak for themselves. So I think that theory went out the door years and years ago.
"And, you know, the multiple Grand Slam titles that we have won, well, I wouldn't have won a single title without him and without his backing."
And while her father's involvement may not be so hands on any more, he continues to impart words of wisdom. "He's just so innovative, and I think one of the reasons I'm still playing some of the best tennis in my 30s is because he built my game and Venus' game. Our foundation was solid and it wasn't weak, so we were always able to grow our game.
"He's just a great coach - even to this day. He wrote me something just the other day, and I just really meditated on it and I thought, 'This is what I need to do, and it really helped me out during the match.'"
As glowing as this reference is, the final word on Williams Sr.'s legacy goes to his daughter's current coach.
"I would say that he's the greatest coach of all time," Mouratoglou said earlier this week. "From what I know, no one else in the history of sports raised two different children to become No.1."