Any skilled/versatile big man with a post game. There's a reason why even players like LeBron can't defend the 5 spot in the NBA.
Why are so many people saying Melo? I think it's clearly lebron or Kevin Steph and James would have too difficult of a time guarding him
LeBron or Durant. LeBron is strong enough to easily get to the rim, and a very good defender. Average jump shooter. Durant is a great shooter, his length makes him an above average defender but he'd struggle against stronger players.