Frances Tiafoe was scheduled to face Tennys Sandgren on Saturday but after testing positive for the coronavirus he withdrew from the All-American Team Cup tennis tournament.
The No. 81-ranked Tiafoe took to social media and wrote that he had been training in Florida and had tested negative there as recently as a week ago.
After defeating Sam Querrey on Friday, Tiafoe was showing symptoms so was tested after the match.
Since testing positive for COVID-19 he has begun the recommended quarantine protocol and will be retested next week.
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