Rafael Nadal in French Open final biggest challenge: Stan Wawrinka

After ousting top seed Andy Murray from the men's singles semi-finals in five sets, third seed Stan Wawrinka will take on Rafael Nadal in the final of the French Open on Sunday. The Swiss ace said that facing the Spaniard in the final of the clay court Major is probably the biggest challenge one can have in tennis. (Video credit: Perform)