Eddie Hearn has been forced to self-isolate after confirming he has tested positive for coronavirus.
The 41-year-old left Matchroom Sport's secure bubble ahead of Joshua Buatsi's bout with Marko Calic.
Hearn tweeted: "Gutted to just find out I tested positive for Covid-19 today and have to leave the bubble immediately.
"Thankfully all other tests were negative. Heading home to rest - catch up tomorrow."
Buatsi's fight is still set to go ahead at Marshall Arena in Milton Keynes on Sunday.
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