You always get somebody on the ground. Look at the UFC. It´s very easy to get someone on the ground in an octagon if you´re a skilled fighter. That´s the reason why Brazilian Jui Jitsu is the most effective martial arts form ever.
A guy like Rickson Gracie(probably the best ever) would need 10 seconds to get everybody involved in a "ground fight".
Pointless discussion.
The fight is not happening, never happened. And as long as there is no fight we have no way of knowing for sure what the outcome will be.
I've seen my fair share of fights where the predicted 'without a doubt winner', 'the can not loose fighter' lost the fight.
I've seen professional fighters (even UFC's) who went up againts marines/seals/rangers etc. and lost.
I've myself been in a (street)fight once or twice against guys more trained then me, better skilled then me and still they lost (one lucky punch is all it takes). Of course I've lost one or two myself.
Hell I even did some tournaments in my day (judo) and as a novice (yellow strip) I became third after beating a couple of experienced guys (brown belts)
So again, it's a pointless discussion to keep refering that someone is the best and will take anyone down. Maybe they will, maybe they won't. But as long as they haven't fought everybody there is no way we can be sure it's true.
So let's burry this discussion and agree that everybody is entitled to his of her opinion and anybody is only as good as his last accomplisment.
Peace