Great white shark
They're more vicious.
This clash has already been witnessed & documented. https://www.youtube.com/watch?v=bpg3ixhIB80
Great whites aren't vicious like killer whales. They kill because you look like easy prey because you're splashing and whatnot; a killer whale, got the name for a reason.
Same as what Sweet Tea said. Plus, I would like to add killer whales are actually very intelligent and are capable of some high forms of intelligence such as in human intelligence.
It wpuld most likwly have its squad behind it, they ate a lot smarter, and could.. heh.. end it quickly.