Pitchers challenging Pedroia ... and winning

These heat maps show Dustin Pedroia's drop in slugging percentage against fastballs over the past four seasons. ESPN Stats & Info

While power is not Dustin Pedroia's calling card, he’s lost nearly 100 points of slugging since 2011.

He’s dropped from .474 in 2011 to .449 in 2012, .415 in 2013 and what would be a career-low .383 this season.

Pitchers are becoming increasingly comfortable pounding the strike zone against Pedroia. In fact, no batter has seen a higher rate of pitches in the strike zone this season than Pedroia.

Pedroia isn’t taking advantage of these pitches in the strike zone. His slugging percentage against those pitches has also decreased each season since 2011, and fewer are turning into home runs.

He is also seeing more fastballs -- and doing less with them. Just as relevant is that more of these fastballs are being thrown in the strike zone, which suggests pitchers are challenging Pedroia to beat them.