Brilliant Frances Tiafoe upsets Juan Martin del Potro at Delray Beach

World number 10 Juan Martin del Potro has been knocked out of the Delray Beach Open by emerging American talent Frances Tiafoe.

Tiafoe, a wild card entry to the event and served a mammoth 17 aces and saved 14 of 16 break points, claimed a 7-6 (8/6) 4-6 7-5 success to set up a clash with eighth seed Chung Hyeon, who defeated Franko Skugor 6-4 7-6 (7/4).

Taylor Fritz secured a 6-1 4-6 6-3 win against Mikhail Youzhny and will play Denis Shapovalov, who defeated Jared Donaldson in three sets.