Arizona Diamondbacks center fielder A.J. Pollock is back, healthy, and confident he can exceed the breakout season he put together in 2015 Healthy A.J. Pollock aims to exceed 2015 breakout season Arizona Diamondbacks center fielder A.J. Pollock is back, healthy, and confident he can exceed the breakout season he put together in 2015 Check out this story on USATODAY.com: http://usat.ly/2lxack2 SCOTTSDALE, Ariz. – One of the best facts about this year’s Arizona Diamondbacks: A.J. Pollock is back, healthy, and confident he can exceed the breakout season he put together in 2015.