Rahman never officially or legitimately knocked him down, plus it was a number of years before Barrett when Tua still had something left in the tank. Barrett knocked him down when Tua was shot. Tua is still shot, I believe, and his punch resistance will only get worse. His best bet at this point is to be fed to one of the Brits, help them get a name on their resume and get a decent payday. The crowd or commentary team won't care how past it he is.
He'll be slaughtered by average fighters at this stage as well. Michael Sprott could probably outhustle him.
Yeah to be honest going off his potential his whole career has been a disappointment. He didn't live up to his talent and I can't see this time around going any better