Del Potro stunned by Tiafoe at Delray Beach Open

Miami, February 23: There was a big upset at the Delray Beach Open after second seed Juan Martin del Potro suffered a last-16 loss to wildcard Frances Tiafoe.

Back in the top 10, there were high hopes for Del Potro this week but the 2011 champion was upstaged by 20-year-old American Tiafoe 7-6 (8-6), 4-6, 7-5.

Tiafoe showed glimpses of his raw talent against Del Potro in his straight-sets loss to the Argentinian star at the Australian Open last month.

But Tiafoe produced a performance beyond his years to reach the quarterfinals, firing down 17 aces and saving 14 of 16 break points as he thwarted the 2009 US Open champion.

Standing in the way of Tiafoe and the semi-finals is South Korean star and eighth seed Hyeon Chung.

Chung, who sensationally reached the Australian Open semis, was too good for qualifier Franko Skugor 6-4, 7-6 (7-4).

Hard-hitting Canadian Denis Shapovalov also advanced with a 6-7 (6-8), 6-4, 6-4 win over Jared Donaldson.

Shapovalov – the youngest player in the draw at 18 years of age – needed two hours, 25 minutes to see off the American.

Next up for Shapovalov is Taylor Fritz, who defeated veteran Mikhail Youzhny 6-1, 4-6 6-3.