Suggested by Anonymous Jozu has a diamond defense which can stop most attacks but to be honest it won’t be stopping Whitebeard at all. Whitebeard’s power was enough to crack the sky itself. Jozu also has no way to land any hits on Whitebeard due to the difference in their attack ranges. Jozu would be down for the count before he even knew what hit him. That’s why Whitebeard is the captain. Whitebeard wins.