The fifth seed faced countryman Steve Johnson, who coincidentally also lost to Federer in the first round in Melbourne. Both men spared little time for commiseration, however, as their battle lasted for over two hours.
It was the 30-year old Johnson who emerged victorious, outlasting Sandgren 6-7(5) 6-3 7-6(3) to win his first ATP Tour-level match of the season.
Johnson now leads his compatriot 2-0 in career meetings, after defeating Sandgren in the Houston final in 2018. The World No.75 next faces Italian Andreas Seppi, who overcame Bosnian Damir Dzumhur 6-3 1-6 7-6(6).
Sixth seed Miomir Kecmanovic dispatched of American Tommy Paul 6-4 6-2, the Serbian advances to face either countryman Danilo Petrovic or Italian Paolo Lorenzi. Kecmanovic reached the semifinals in Doha earlier this year and the 20-year old will hope to do one better this week in New York.
Former World No.8 Jack Sock received a wild card entry to this event, but the 2017 Paris Masters champion seems to be stuck in a rut. Playing in his first singles match in 2020, the American fell to unseeded compatriot Marcos Giron 3-6 4-6 in an hour and 16 minutes.
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