Heyward started slow but found way to make it work in 2015

Jason Heyward's 2015 is the classic example of the idea of not judging a player by his April.

Heyward went from struggles to stardom, capped by a grand slam in the St. Louis Cardinals’ win over the Pittsburgh Pirates on Wednesday night that clinched the National League Central title. The adjacent chart shows the difference in his numbers since the calendar turned to May.

Heyward is arguably the team MVP. His 6.0 Wins Above Replacement are the most among Cardinals position players by a considerable margin. Matt Carpenter, who has had a terrific September, ranks second with 3.4.

Though Heyward is not the power hitter he was as recently as 2012, when he hit 27 home runs (he has 13 this season), the other aspects of his game are strong. He’s on the verge of finishing with the highest batting average (.292) and second-highest on-base percentage (.358) of his six-year career. His 23 steals (in only 26 attempts) are a career high.

Has anything changed?

The most notable thing about Heyward’s hitting compared to previous seasons is how he handles inside pitches. Those had been an issue for him in the past, and he has fixed it by letting more of them go.

He went from swinging at 47 percent of inside pitches (defined as being on the inner—third of the plate or off the inside corner) in 2013 to 32 percent in 2015. Over a full season, that’s about 125 fewer swings.

What he has swung at, he has hit. Heyward has 39 hits against inside pitches. He had 36 last season, despite taking 39 more swings.

The defense

Heyward entered the day with 23 Defensive Runs Saved, including nine in the month of September. The former ranks fourth in the majors. The latter is tied for first at any position with Cubs infielder Addison Russell.

Over the past three seasons, Heyward has 65 Defensive Runs Saved, second in the majors to Andrelton Simmons.

Heyward showed off his glove in Game 2 of Wednesday’s doubleheader, with a diving catch to take a hit away from Francisco Cervelli and a leaping catch at the fence to rob Michael Morse of extra bases.

Looking ahead to October

Heyward’s postseason history is a small sample, but a shaky one. He’s a .154 career hitter with six hits and 16 strikeouts in 39 at-bats.

Though small sample sizes on batter-pitcher matchups aren’t necessarily predictive, Heyward would be a confident hitter if the Cardinals faced the Cubs in the National League Division Series. He’s a .500 hitter (9-for-18) against Jason Hammel, .417 against Jon Lester (10-for-24) and .333 (6-for-18) against Jake Arrieta.