It wasn’t fixed but you could tell there was some kind of bonus arrangement for letting it go a certain length of time. It was either near the end of round 1 or 2 Rickson kept asking how much time was left while he was mounted (IIRC). Finally just before the round ended he finished the fight.
I think the same kind of arrangement happened with Cro Cop vs. Yoshida. CC kicked him a bit too hard in the leg and Yoshida went down. You could see this “oh shit” look in Cro Cop’s face and he immediately dived into his guard and covered up. There was no reason for him to do that unless there was an agreement to have a certain amount of groundwork take place.