Shelby Miller tinkers with a sinker as his fourseamer fades

Every year, the St. Louis Post-Dispatch offers readers must-read reporting in their opening-day issue. This year, ace Cardinals scribe Derrick Goold dug deep into the Cardinals' drafting and development of young arms. Way back at the start of the season, you may recall, one of the Cards' strengths was thought to be their young pitching depth. One of the poster boys for that depth was Shelby Miller, fresh off a third place Rookie of the Year finish—even if his late-season fade and ultimate October disappearance cast a shadow over his excellent premiere season. Goold writes about how the selection of Miller, who was selected out of high school, was a watershed moment for the Cardinals:

Leading up to the Miller pick, the Cardinals had earned a reputation for avoiding the draft’s radioactive risk, high school pitchers. In 2004, they didn’t take a preps pitcher until the 46th round. In the three drafts before Miller’s the earliest the Cardinals selected a high school pitcher was the seventh round. During those years the Cardinals hoarded intelligence, researched injuries and data-mined for clues that would change how they scouted and harvested pitching.

When team officials presented chairman Bill DeWitt Jr. with a list of players in the 2009 draft they eyed for the 19th pick, there was the culmination of this effort near the top: Shelby Miller, a high school pitcher from a small town in Texas.

"By the time we picked Miller, I think our knowledge base in at least how to avoid the high-risk players had evolved to the point where we felt more comfortable fishing in those waters," said Jeff Luhnow, the Astros general manager who oversaw the Cardinals’ draft until 2011. "He had the delivery. He had the pitches that we thought could develop. The size. The makeup. We had learned from our mistakes."

In the midst of the Tony La Russa and Dave Duncan era, the drafting of Miller in 2009 represented a break of sorts from the democratic groundball-inducing philosophy of the pitching coach who time and again impressed upon fading veterans the virtues of throwing sinkers and pitching to contact. Miller didn't possess a sinking fastball of the bat-finding variety. Rather, it was Miller's fourseam heater that enticed the Redbirds into selecting the prep Texan. Early in the 2013 season, Miller's fastball even led Duncan himself to say that pitchers who could throw heat like Miller didn't need to pitch to contact. As reported in Sports Illustrated by Ben Reiter:

The 6'3", 215-pound Miller is also a terrific athlete—he played football both ways at Brownwood (Texas) High—and when Duncan got a look at the way he threw a four-seam fastball in his first spring training, the promoter of the two-seamer delivered a simple message. "I said, 'Don't let anybody f--- you up,' " Duncan recalls. " 'If somebody wants to start making changes in what you're doing, call me.' Different guys have different abilities. But most guys don't have Shelby's."

"That's exactly how the conversation went," confirms Miller, who hasn't had to give Duncan a ring. "Nah, I don't even toy with any two-seamers."

"If it plays," says Lilliquist, "it's going to play."

As Joe broke down during the offseason, Miller heeded Duncan's advice during his first big-league season, relying heavily on his fourseam fastball. While posting a 3.06 ERA, 3.67 FIP, and 3.73 xFIP, Miller threw his fourseamer an eye-popping 73.6% of the time. And understandably so—opposing hitters whiffed on Miller's fourseamer 23.73% of the time, the six-highest whiff rate in all of baseball for a fourseamer for a starter.

But the effectiveness of Miller's fourseamer has fallen off during his sophomore campaign. The opposition is whiffing just 17.02% of the time. Overall, Miller's whiffs have dropped and his K% has seen a corresponding dip. In 2013, Miller's 23.4% strikeout rate sat comfortably above the cumulative National League starting pitcher rate of 18.9%. This year, Miller's strikeout rate has fallen to 15.8%, well below the NL starter rate of 19.3%. Miller's walk rate has also shot up from 7.9% in 2013 to 10.6% in 2014. Not surprisingly, the righty's ERA, FIP, and xFIP have ballooned to 4.26, 4.80, and 4.71 respectively.

In Reiter's Sports Illustrated piece, Duncan elaborated on when pitchers should turn to sinkerballing:

The problem was that almost every pitcher was reaching the major leagues by virtue of his four-seam fastball. "It's really a comfortable pitch to throw, the grip feels good, the release feels good, everything about it feels good," Duncan says. But most of those offerings were no longer good enough. "The majority of the pitchers that you came across fit into the category of average velocity, 90- to 92-mile-an-hour fastballs, straight as a string. And 90- to 92-mile-an-hour fastballs that had no movement on them were basically a hitter's delight."

Duncan's genius did not lie in his realization that his pitchers should minimize, and sometimes abandon, their four-seamers for two-seamers—either a cutter, gripped slightly on the outside of the baseball, or a sinker, gripped slightly on the inside—which impart a downward movement, thereby yielding more grounders. His genius lay in his ability to persuade pitchers to try it, and to help each get the hang of it in his own way. "They gotta tinker," he says. "That's the only thing that works."

With Miller's effectiveness dipping to Duncan reclamation project levels, Miller began to tinker with a sinker. The righty unveiled his new offering over the weekend in Philadelphia. Rick Hummel reports in the St. Louis Post-Dispatch that Miller experimented with a sinker grip he learned from Justin Masterson. According to the invaluable Brooks Baseball, Miller had barely thrown a sinker all year until facing the Phillies on August 23, when he tossed the sinker and fourseam each 40.82%. From the Hummel article, it seems that manager Mike Matheny is all for Miller expanding his arsenal:

Manager Mike Matheny said: Pitching coach "Derek Lilliquist continues to challenge these guys on how to help their repertoire. That's a pitch Shelby really never has found a great feel for. He's very adaptable in that regard."

Matheny said he was most impressed that Miller would try something different this late in the season. "This could be very, very big for him. It was a bold step for him to jump right in and use it," said Matheny.

"It's time to keep going."

Apparently Miller and Lilliquist recognized that Miller's fourseamer was no longer playing—to hark back to the pitching coach's quote to Sports Illustrated—and decided to tinker in the way that Duncan might have encouraged. After a lackluster sophomore year to date caused due to an increasingly ineffective fourseamer, what does Miller have to lose by reinventing himself in the mold of Duncan?

correction: I originally wrote Shelby's usage of his sinker and fourseam on the August 23 game as 16.67% and 14.29% respectively. This has been corrected to each pitch used 40.82%.