Boxer Mikaela Mayer tested positive for the coronavirus and will miss her scheduled junior lightweight bout on Tuesday against Helen Joseph.
The 10-round bout was scheduled to be one of the featured fights on the Top Rank card at MGM Grand Garden Arena in Las Vegas.
Mayer, who turns 30 next month, made the announcement on social media on Sunday and called her positive test "a complete surprise" since she believed she was taking all required precautions to stay safe from COVID-19.
"I am currently asymptomatic and am quarantining at an off-site location per recommended guidelines," Mayer said.
"The rest of my team tested negative and they are all in good health. I was really looking forward to bringing back boxing for all of you and I'm disappointed for myself, my team, my supporters and for my opponent, Helen Joseph, who worked just as hard to be here this week and put on a show for everyone."
Under Top Rank rules, Mayer can't be retested to determine whether the test was a false positive. One positive test means the fighter is removed from the scheduled bout and quarantined away from the bubble created at the MGM.
Mayer's manager, George Ruiz, told ESPN that Mayer wants to fight later this summer once her COVID-19 tests are negative.
Tuesday's card is highlighted by a bout between WBO featherweight champion and U.S. Olympian Shakur Stevenson and Puerto Rico's Felix Caraballo.
--Field Level Media