Tres didn't need to anchor his feet to the floor, because he had friction and good shoes on which would allow him to push forward as he felt the opponents hands grab onto his jacket in an attempt to push him away. Tres due to his strength would only need one foot to push in the opposite direction of the direction his opponent was trying to push him in, plus his weight, would put the current position in dead lock.
Also as the opponent began to push, Tres's left arm would grab around the inside of his opponents upper right thigh, giving Tres something to pull on.
Besides, the jacket was open and wasn't tight against Tres's body...all the opponent was doing was pulling the jacket lower on Tres's body and the jacket was ripped on the left side, so rather than the jacket being a good point to manipulate Tres's body on the left side, the jacket would simply rip instead of giving the opponent any control.
Tres's body was not the thing going up, and therefor would do little to keep his legs away. Tres's hips were the factor that allowed Tres to knee his opponent in the face, with his right knee, which he would still be doing all along. Tres's body would push down on the opponent to keep him from escaping while his hips (right side) would come up and smash towards the opponents skull.
While Tres's head would stay looking down at the opponents lower abdomen, because of his attempt at separating them failing, the opponents hypothetical thought of kicking his right leg up to Tres's face would be hard unless the opponent was really, really, flexible.
So yeah...
SMASH SMASH SMASH, went Tres's right knee.
"Oh, Oh,*Smash* I'm sorry, *SMASH* maybe me laying *SMASH* on top this guy *SmASH!* and beating his face *SMASH!* with my knee is too *SMASH!!* damn complex for you *SMASH!!!* people", Tres was obviously pissed about something.
