The Scottish Government has poured cold water on hopes of crowds being allowed into sports grounds before October.
Reports have claimed that Celtic Park could be half-full before the end of August, but national clinical director Jason Leitch believes only small-scale tests will be permitted before limited crowds return in the autumn.
The Scottish Premiership is set to kick off behind closed doors on August 1, while rugby will return with two Guinness PRO14 fixtures between Glasgow and Edinburgh on consecutive weekends in late August.
Professor Leitch told BBC Scotland: "I think we're seeing pretty much no chance of crowds in August. I can't imagine physically-distanced crowds in August or September. I might be wrong and with a fair wind we might get there.
"I think we might run some test events during that two-month period – it might be a big match but a small test-event crowd. Either rugby, football, maybe both.
"And then thinking about into the autumn and winter, I would hope if things remain good, then we might be able to get back to physically-distanced crowds."
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