The Professional Tennis Players’ Association accuses the sport’s organizers of engaging in anticompetitive behavior and unfairly restricting players’ earnings.

Will Djokovic and Swiatek turn their season around? Can Andreeva continue her incredible run? The biggest questions as the Miami Open begins.

Some top tennis professionals and a group co-founded by former No. 1 men’s singles player Novak Djokovic and hedge fund manager Bill Ackman are suing the sport’s governing bodies for allegedly running ...