one thing people forget in the "brock vs (hard hitter)" style threads is that Brock didn't automatically fall down and lose as soon as he was hit hard.
Instead his first reaction was to go for Desperation Takedowns
and we're not talking about some sloppy no hope to land takedowns either...these were GOOD takedown attempts.
When Carwin first clipped Brock, Brock pushed him half way across the cage and almost took him down (Carwin pulled a whizzer and barely avoided it)
when Carwin rocked him again (the famous uppercut that made Brock jump) Brock went for TWO takedowns before he turtled.
Against Cain from the time he got hurt to the time the fight was finished, he went for about 3 takedowns and a submission (and earlier in the fight, he landed a takedown as cain was hitting him)
Against Mir, he got hurt by a knee and immediately took Mir down.
Against Herring, he got hit by a solid punch right on the chin and in response he fucking TACKLED Heath Herring--it literally looked like a football tackle.
and of course for every knee Overeem landed, Lesnar went for a takedown.
So it is seriously not a matter of "all (hard hitter) has to do is touch him once!" like people always say. It's more like "all (hard hitter) has to do is touch him once and then avoid the onslaught of takedown attempts and then continue to hurt him a few more times"
way easier said than done