The Diamondbacks changed hitting coaches on Wednesday, promoting Rick Schu to replace Kevin Seitzer. Arizona trails San Diego by 3 1/2 games in the NL West. The Diamondbacks have stayed in contention despite a .248 team batting average. Schu, in his 10th season with the Arizona system, was the organization's hitting coordinator. Seitzer was in his first year as the Diamondbacks hitting coach.