The Polish juggernaut was joined by her coach, who won coach of the year.
The 24-time major champion gives rare insight into his champion's mentality and his relations with Federer and Nadal.
"They are the highest icons of our sport," Roger Federer said of his Big 3 rivals.
Klugman took out American Tyra Grant in the final.
"My cancer is back," Hall of Famer Chrissie Evert announced.
Stephens, a former champion, and Sakkari, a perennial Top-10 talent, join a field that already includes Jessica Pegula, Madison Keys and Ons Jabeur.
The American rises to the top of the list thanks to $16 million in endorsements and another $6.7 million in prize money.