Lance Bass -- Touchdown Dance Training ... With Detroit Lions Star

Detroit Lions TE Joseph Fauria can say bye, bye, bye to his old touchdown dances ... 'cause he's got a brand new set of moves now -- courtesy of former 'N SYNC member Lance Bass.

Fauria -- who famously busted out all sorts of boy-bandish style celebrations during his rookie season -- was set to showcase some of his new moves during a bit for Fox Sports 1 ... when Bass showed up to show him a new trick or two.

Check out the video, Lance lays out some classic 'N Sync choreography ... and Joseph hilariously does his best to keep up ... but it's obvious Lance is the expert in the dance dept.

Next up? Blocking Ndamukong Suh in practice ... good luck Bass.