Undefeated 130-pound contender Mikaela Mayer has tested positive for COVID-19 and will not fight on Tuesday in Las Vegas.

Mayer, who is 12-0 as a professional, was scheduled to face Helen Joseph in a scheduled 10-round bout on the undercard of WBO featherweight beltholder Shakur Stevenson’s ESPN-televised non-title junior lightweight bout against Felix Caraballo.

Mayer, a 2016 Olympian, was shocked by the test results.

 

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I am heartbroken to report that I will no longer be fighting on Tuesday’s Top Rank card due to a positive result in my COVID-19 test yesterday. It came as a complete surprise. I am currently asymptomatic and am quarantining at an off-site location per recommended guidelines. 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. After two hard back-to-back camps, not being able to step in to the ring both times, you can imagine how disappointed I am. However, these protocols were put into place for a reason and it’s more important to care about the health and well being of my team and the people at this event. So I am complying with the rules set forth by the Nevada State Athletic Commission and Top Rank to keep everyone safe. I will just have to take a quick break but I will be in the ring soon. I appreciate all the love and support. Please tune in to ESPN on Tuesday night and support the card and all of the fighters. Boxing is back and I’ll be back.?? #boxing

A post shared by MIKAELA MAYER (@mikaelamayer) on Jun 7, 2020 at 11:48am PDT

“It came as a complete surprise. I am currently asymptomatic and am quarantining at an off-site location per recommended guidelines,” Mayer said in a statement.

Top Rank Vice President Carl Moretti told The Ring on Sunday afternoon that there will not be a backup opponent in place.

“We will just try to re-schedule (the fight at a later date),” Moretti said.

Mayer’s team, however, all tested negative for the virus.

“The rest of my team tested negative, and they are all in good health,” she added. “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.”

Mayer last fought on Oct. 26 when she stopped Alejandra Zamora in six rounds.