Shaquille O'Neal and Kobe Bryant
The Big Aristotle and the Black Mamba won three NBA titles together, and Shaq was the Finals MVP each time. Perhaps that's why he famously freestyled that Kobe couldn't win a championship without him, going on to inquire of Kobe, "tell me how my ass taste." Kobe did prove Shaq wrong about the championship thing, winning two more all on his own (or at least without the Diesel), but it's hard to gauge if even that has settled the score. While the two now dismiss their feud, you don't get the sense there's any love lost.