If you have an abundance of slow twitch muscle fiber and your opponent has an abundance of fast twitch muscle fiber - then all the 'preperation' in the world is not going to change the outcome of a 'takedown clinic'.
Sometimes you just come up against a stronger, quicker 'horse'. No shame in that.
20 years ago I coached a kid going for his third straight state title. He put on a take-down clinic. His opponent 'took his beating like a man'. I got it on tape. For a lack of a better adjective - his (the one who lost) reaction was 'cute'. After getting teched in less than two minutes, he had a silly grin on his face as he shrugged his shoulders, raised his hands up and looked at his coach. Kind of a "what the heck could i do coach?" expression. Having wrestled his opponent several times myself - i felt the exact same way. I NEVER took him down. I could beat our undefeated 171 pounder because he was 'slow' like me. But, I had no chance EVER against our stealthy little 145 pounder. And, i was a solid 160 back then. I tried and tried. Every time I thought I had him - DARN! RATS! I had given up two AGAIN!!! After a while I just quit wrestling him! Too frustrating! ;-)
Back when Neb. was a power-house in football, Coach Osborne got the idea. He went out and recuited speed. THEN, he won his national titles. you can't coach quickness. Either you have it or you don't. I don't care how good of defensive technique you have, it would not have done you much good wrestling say John Smith in his prime. EVERYBODY knew the low single was coming. NOBODY could stop it . . .
Again, no shame in getting schooled by a stud. Take you 'beating like a man', learn what you can from it, AND MOVE ON!