Memphis has nine players who have 18+ minutes per game and have played more games than Zach, and that does not include Morant or Smart. Huff's minute numbers are dwindling. They want Zach to be an enforcer and a rim protector. His ORs are fantastic, and he boxes out his man while other teammates come under and grab rebounds. However, he still is the rebounding leader.
IMO, his face mask is hampering him and has affected his hand-eye coordination. Instead of teammates who get the ball inside to him, they have to make their ballet moves, and when met, they make a circus pass to him that will improve once the mask goes.
Right now, Missi is the stat leader because he plays for a terrible team, and this is true with Ware, who recently has been putting up fine numbers for a lousy team, but my money is on Zach once he is completely healthy. Another notable is that he has played very well in back-to-back games, showing his fine conditioning.