Joey Fatone is itching to collect $1k from our photog, who bet him that 'N Sync will take the stage with Justin Timberlake during the halftime show at the Super Bowl.
We got Joey Friday night at the Leather and Laces Party in Minneapolis and he's stickin' with his story that Justin will perform solo, although he's not ruling out a surprise appearance by Janet Jackson.
Joey offers evidence ... singers who perform for a billion people typically don't go out and party 2 days before the big game.
Joey might have a point ... we got video of Justin's rehearsal, and he's on stage like a lone wolf.