World champion Josh Taylor fears it will be hard to motivate himself for the "glorified sparring" of boxing behind closed doors.
The Scot was meant to defend his World Boxing Association and International Boxing Federation super-lightweight titles against Thai opponent Apinun Khongsong in Glasgow on May 2.
But the outbreak of the coronavirus has put paid to that bout, with Britain in lockdown.
And even when UK government restrictions are lifted, the British Boxing Board of Control has warned planned bouts may be subject to further delay if they risk placing additional strain on the National Health Service.
It looks increasingly likely that any initial resumption of major sport in Britain, including boxing, will be without spectators.
But Taylor said the absence of a crowd could deprive him of a competitive edge.
"It would be a bit like a glorified sparring match if there's only 50 people in the building," Taylor told BBC Radio's boxing podcast.
"It's not ideal. I think for me it would be quite hard to get up for.
"If the crowd wasn't there you'd lose that wee bit of nervousness walking out. Just as you get ready to walk out, you see the crowd and think 'this is it man, what I live for' and there's no way I'm getting beat. It fires you up."
Nevertheless, Taylor said he would consider taking a fight even if there were no spectators.
"But, on the other side, I go back to my amateur days when there were only a couple of hundred there. So I'd go back to that experience to make sure I win the fight."
Taylor has a perfect professional record of 16 victories, 12 inside the distance.
But the 29-year-old needed a majority decision last time out to beat Regis Prograis in October's final of the World Boxing Super Series.