Tim Tebow -- My Underwear Sponsor Jockey Still Has My Back ... and Fr

He's getting screwed by the Broncos ... but Tim Tebow can still count on one of his employers to cover his ass -- his underwear sponsor.

Though it's unclear where Tebow will end up after the whole Peyton Manning shake-up ... the people at Jockey tell TMZ they will stick with their spokesman no matter what.

A Jockey rep says, "Jockey brought Tim Tebow on as a spokesperson before he took his first professional snap and even before he finalized his contract with an NFL team. Jockey supports him 100% and we look forward to continuing our great relationship with Tim."

Finally, support where it counts.