You know about Brachiosaurus, but do you know about Brachiosuchus? This huge (7 m) crocodylomorph lived in what is today Sudan near the end of the Cretaceous period. It is notorious not just for its size but for its very long and robust arms, far bigger than its hind limbs, which suggest it was probably swimming in a manner unlike any modern croc, using the arms in a much more active manner and probably being a much more maneuverable swimmer. Not a beast you'd like to have a swimming competition with even if it's long narrow snout suggests a mostly piscivorous diet.

https://www.deviantart.com/hodarinundu/art/Diving-with-Brachiosuchus-901279581