A 2000 lb crocodile doesn't have an advantage in water over a 500 lb lion ?
Sooo a croc averages some 2,000 lbs now? Thought these were record breakers:
Google
More like 1,000 lbs if your prime specimen, a 2,000 pounder is a freak sized croc, your prime sized lion at 600 lbs can take a thousand pounder croc, most sub-adult weights now days have lions at 600+ lbs:
http://www.thecoli.com/threads/barbary-lion-vs-siberian-tiger.419272/page-14
If a lion has to swim and cannot touch the bottom of the river..advantage is All in the crocs favor.
Only time you see a lion get away is in those shallow rivers where it can touch ground and use its legs..where it has to swim using its legs and paws and has no leverage it has no chance against a croc....
The reason you don't see videos of it cuz lions know to stay away from deep waters where's there crocs.They don't do those same migrations...
Again, doesnt really matter, only in the crocs element he can win, just like cobras one bites, killer whales in the water, lions on land, in their own element, they win, in a fair scenario of shallow water, a big lion has more advantages over a big croc. The croc only has one main weapon his bite, and maybe his tail...the lion has not only a powerful bite as well, he has claws and on top of that brute strength, he can smite in the skull of nearly any animal short of a hippo, rhino or elehant, they kill bears with one blow to the head and back, bulls by breaking their necks, and even a few accounts of lions smashing in the heads of crocs.
So I lean with the one with more advantages, not the one that relys only on one method, if he cant land that one shoter, hes as good as dead...even if he lands the one shot bite, theres photos of lions shrugging off a bite to the face...a croc can be killed at the head, and underside as well, by pinning him down, controling from the back, or getting at his throat, all which has been shown the lion already did to crocs. The croc is not even the big dog of the african rivers, that title belongs to the hippo.