In a statement LCR confirmed:
Unfortunately, today a member of HRC team working for LCR Honda has tested positive for COVID-19, being immediately isolated. The three members with Category 1 contact have been isolated and tested, returning negative results.
They added that HRC had deployed new technicians for Sunday's race to support their two riders, Briton Cal Crutchlow and Japan's Takaaki Nakagami.
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Now returning to the team after he was ruled out for two races, thanks to an arm injury, Crutchlow admitted the result was a setback.
However, he added: "But it doesn't stop us from working hard and continuing to do our jobs in the garage. We've all today had another test and everyone in the garage has tested negative.
"I don't know how they do it, but it's a fast test and we had the results within in one hour. I had two tests, just before I went out, the nose was constantly running because you had the swab up the nose twice.
"But, it's OK, it's part of it, and this shows how much we want to do it because we go through it all the time."
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