Alexander Zverev collected his fourth title of the year by outclassing Kevin Anderson in straight sets in the final of the Citi Open.
Zverev had already won in Montpellier, Munich and Rome this year and he again demonstrated his vast potential in a straightforward 6-4 6-4 win over Anderson on Sunday.
Victory was rarely in doubt for the fifth seed, who did not need to be at his best to comfortably beat Anderson inside 70 minutes in Washington.
And with two-time winner Novak Djokovic and defending champion Stan Wawrinka missing the US Open due to injury, Zverev must be a contender for the last slam of the year.
Zverev tested Anderson's booming serve immediately, but the big South African, playing in his first final for two years, survived a pair of break points to hold.
The German nudged ahead in Anderson's next service game, however, a well-timed lob sent into the net to finally secure the break at the fifth time of asking.
Zverev did not face a single break point as the 20-year-old serenely closed out the set thanks to Anderson sending a backhand wide.
The power and accuracy of Zverev's groundstrokes was proving too much for Anderson, who was again broken in his first service game of the second set when he missed the baseline.
Zverev was almost teasing Anderson at times, moving his opponent, 11 years his senior, around the court with ease, despite the 15th seed getting a series of lucky breaks via the net cord.
Although Anderson made him serve for the title, the precocious German showed no nerves in taking his first match point to add another trophy to his fast-growing collection.