Show your support for this star player with authentic Oakland Athletics A.J. Puk jerseys and more. Shop the best selection of A's A.J. Puk apparel and gear from MLBShop.com. Proudly display your favorite player's number at the next game with official A.J. Puk t-shirts, jerseys, and more. Gear up with the newest additions of A's A.J. Puk merchandise from the official Online Shop of the MLB.