Exclusive | Madison Keys bringing her late-career breakthrough to US Open after winning elusive Grand Slam

Madison Keys started her tennis season on the highest possible high.

After coming close as a 2017 U.S. Open finalist, the 30-year-old finally won her first Grand Slam title at the Australian Open.

Not only that, she defeated three-time Grand Slam champion and defending Australian Open champion and world No. 1 Aryna Sabalenka in a three-set thriller, 6-3, 2-6, 7-5.

It was the sweetest victory imaginable for the world-No. 6 American, and she has yet to even reflect on the stunning late-career breakthrough.