Player growth and development usually occurs slowly over multiple seasons, but in the case of Stefanos Tsitsipas and Aryna Sabalenka, they've come of age before our very eyes this US Open Series.
Tsitsipas has proved he is a major force to be reckoned with right now by learning and improving with each match. After putting together a solid week to reach the semifinals in Washington D.C., the Greek struggled against eventual champion Alexander Zverev, falling in straight sets.