The Portugal attacker has battled from a preseason knee injury to feature in the final games of the season.
Zola told whufc.com: "I tell you, if I could pick out one player to score the first goal, it would have been Luis, big time. I am really pleased for him because he's a player we've missed very much.
"He was and he is an important player on and off the pitch. You need players like him."