Grachev is a former world champion in Muay Thai, and he fights like one. His stance is very straight, with a loose, high guard. He has almost no head movement but picks off punches well with his gloves.
His apparent lack of defense is deceptive. Grachev reads his opponents well and has very good timing, so one of his primary defensive techniques is to counter-attack at the first sign of offense from his opponent.
This is another trick that I think follows Grachev from Muay Thai, where traditional western boxing defenses, like bobbing and weaving, move a fighter into an even more dangerous line of attack.
Grachev is a very accurate puncher and leads well with both hands. He throws a nice lead left hook and a very effective lead right to both the body and head.
Grachev is a strong fighter and extremely durable. He can take a shot and come forward.
Rodriguez has a very strong amateur background, and his boxing is technically solid. He has good head movement and changes levels well.
Rodriguez throws quick one-two combinations. He is a strong puncher and counters well off a slip.
Rodriguez has fought a wide variety of tough prospects and demonstrated a strong boxing IQ. He is very good at reading what his opponent is giving him and reacting accordingly. He fought a much different fight against the 6'4” Pryor than he did against the stocky, athletically explosive Rosinsky.