Suggested by Anonymous Ryuma is a super talented swordsman and we have yet to see him at his best. So that puts him at a disadvantage but at the end of the day he isn’t quite ready for Whitebeard. Whitebeard has fought many different fighters with the sword in his day and some of those certainly surpassed Ryuma. Ryuma will be kept on the defensive here without much opportunity to launch a true counter attack. Whitebeard wins.