Watch Challengers for Free: How to Stream the Movie Online at 123Movies. . Tennis player turned coach Tashi has taken her husband, Art, and transformed him into a world-famous Grand Slam champion. To jolt him out of his recent losing streak, she signs him up for a "Challenger" event — close to the lowest level of pro tournament — where he finds himself standing across the net from his former best friend and Tashi's former boyfriend.