MLB Power Rankings: Detroit Tigers slip again

18 of 31

Sep 2, 2015; Oakland, CA, USA; Los Angeles Angels center fielder Mike Trout (27) at the wall as catcher Josh Phegley (not pictured) hits a two run home run during the first inning at Coliseum. Mandatory Credit: Kelley L Cox-USA TODAY Sports

14. Los Angeles Angels (69-68)

According to Fangraphs, Mike Trout is just an average defender, entering Sunday with 3.0 defensive runs saved, 10th among 22 qualifying major league center fielders. His ultimate zone rating of -1.2 and overall defensive rating of 0.7 ranked 13th.

Can someone explain what that means?