Can't the basketball players just play with a mask?

Can't they just design a mask that doesn't fall off, and then sure it'll be harder to breathe, and the person who originally had it would be quarentined, but the others would just wear masks. Is this a reasonable thing? Why or why not?

EDIT: Not instead of not having fans, but instead of comole canceling. They cancelled the NBA, NCAA is just having no fans which makes the most sense to me.