The Cuban came under some pressure in the first round but managed to subdue his opponent and open up a four-point cushion.
La Cruz had settled into his rhythm by the time the second bell had sounded and he took a stranglehold on the contest.
He found the target with a powerful right uppercut that scrambled Almatbouli's senses, before landing with another punishing blow that underlined his dominance.
La Cruz had stretched his lead to an incredible 13 points as they entered the decider and he did not relent with his assault.
The judges awarded him a 25-8 decision.