So I was was considering a three-way fight between Gaara, Sandman and Crocodile (from One Piece...think Lex Luthor as a pirate with Sandman's powers.)
The outcome wouldn't change much, (it's a tie unless Gaara can control both Sandman's and Crocodile's sand) though, Crocodile, being the intelligent guy he is, could probablythink of some way to turn the fight in his favor. Also, Gaara might be vulnerable to Crocodile's "remove moisture from the human body" trick.