The Pirates led all clubs with a 51.1 percent ground-ball rate from 2013-15, one of their biggest strengths as they made the postseason three straight years and posted the Majors' second-lowest ERA during that stretch. They induced grounders at a 46.9 percent clip this year, tied for third in the Majors but still a noticeable dropoff.
"I do think it's something that we're going to keep as one of our cornerstones," manager Clint Hurdle said.
Some of this year's change was by design. Most of the league has developed a similar affinity for ground-ball pitchers, making those arms (and their sinking, two-seam fastballs) more difficult to acquire.