For several years now, it's been common knowledge among One Piece fans that the strongest members of the Straw Hat Pirates are Luffy, Zoro and Sanji. They were known as the Monster Trio, and together, they took down many-a foe. However, a recent addition to the crew has thrown a wrench in that accepted norm: Jimbei the Fish-Man. Now, there's a controversy among the fandom as to who should take the third spot in the top three fighters.
Vinsmoke Sanji has been the third strongest member of the crew since he joined after serving as a sous chef on the restaurant ship The Baratie. Once he joined Luffy on his adventures, it quickly became clear he was a high-class fighter as well as a high-class chef. Sanji would handle some of the lower level fighters so his captain could focus on the leader, while Zoro handled the second-in-command or the next strongest fighter. Together, they would take on numerous foes and come out successful in their ventures.
During the two year time-skip, Sanji also learned he can strengthen the power of his attacks by generating flames from his legs. This has only increased his strength as a fighter, with his new techniques showing that he is a capable combatant. He's able to use the flames to not only cause radial damage, but also to deflect attacks from enemies.
Jimbei, however, has disrupted that. His addition to the Straw Hats now has One Piece fans wondering if he will take Sanji's place as third strongest. He was once captain of the Sun Pirates, a crew made-up of Fish-Men. After he became the crew's second captain, he eventually earned the title as one of the Seven Warlords of the Sea. Jimbei was able to go head-to-head against Ace, a Logia Devil-Fruit user, and match him blow for blow. The two fought for five days before the fight ended in a draw. Even among his fellow Fish-Men, he is considered one of the strongest. He is a master of Fish-Man Karate, so much so that he doesn't even need to make physical contact with an opponent to send them flying across the battlefield.
So who takes the mantle of the Straw Hats' third strongest fighter? It's very close, but Jimbei has the advantage of time and experience over Sanji, honing his skills and evolving them into what they are today. Sanji is still discovering what he's capable of, and while he isn't weak by any estimation, he's still very young. He only recently discovered his fire powers, and while he's learned to use them in battle, he still has time to take them further.
Jimbei has had that time, though there are still ways for him to also develop his powers. Both use pure martial abilities in their fights, but Jimbei is a master of his art. Sanji, while a master of the culinary arts, could elevate his skills and learn new ways of combining his kicks with his flames. Until then, Jimbei has the slightest of advantages over him as the third strongest Straw Hat in One Piece.
