In a new interview, Mouratoglou talked about Williams and her difficulties at Wimbledon.
The 21-year-old is well outside the top 100, and without an agent now.
Former No. 1 plays WTT for first time in four years.
The two stars come from different sporting worlds, but joined forces for a unique battle.
A treasure trove of some 70-plus tennis posters will be up for auction.
PlayTennis.com is giving fans a chance to win tickets to this year's US Open event.
Victoria Azarenka will join Bryan Brothers at V-Grid Tennis Fest benefiting the Bryan Bros. Foundation.