Rockets coach Kevin McHale has always marveled at Dwight Howard’s ability.

Now, the brilliant former Celtics big man will have the opportunity to mold a player he considers one of the dominant centers in the NBA.

The 6-11 Howard signed a four-year deal Saturday morning to officially join McHale’s Rockets. That gives the Rockets an edge against almost every other team in the NBA, but only, McHale said, if he fulfills his responsibility.

“My job is to put him into positions to succeed. That should be easy,” McHale said. “I told him if he’s not dominating at both ends of the floor in the paint, I’m not doing a good enough job getting him to play to his potential.”

Though Howard, 27, played in 76 of 82 regular-season games with the Lakers last year, he is coming off one of his most frustrating seasons. He suffered through back and shoulder injuries while Los Angeles struggled and barely made the playoffs.

Howard had his lowest rebounding average since 2007 and his lowest scoring average since 2006.