The St. Louis Cardinals’ torrid offense deservedly received most of the credit for the team’s success this season. However, it’s doubtful they would have finished with the best record in the National League without the contributions and overall consistency of their rookie pitchers.
Using 12 different rookies during the regular season, the team’s collection of promising young arms posted a 36-22 record with a 3.17 ERA, 8.79 K/9 and 2.99 BB/9 over 553.2 innings.
Among those rookies are homegrown right-handers Shelby Miller and Michael Wacha, both of whom ranked as top-50 overall prospects heading into the season.
After reaching the major leagues as a September call-up in 2012, Miller was a fixture in the Cardinals starting rotation this season, making 31 starts and posting the 10th-best ERA (3.06) in the National League. Wacha, meanwhile, was a midseason call-up that bounced between starting and relieving before joining the rotation full time in September. And in the final month of the season, they combined to go 5-1 (10 starts) with a 2.23 ERA over 60.2 innings.
Given their success amid a heated playoff race, Miller and Wacha will likely start for St. Louis in the NLDS against the Pittsburgh Pirates and potentially beyond.
Manager Mike Matheny had some important advice for his rookies heading into October (h/t to Derrick Goold of the Herald and Review):
"It's still 60 feet, 6 inches (from the mound) and 90 feet to each base," the manager said. "They need to trust that. The expectation isn't any different from me or the coaching staff, and it shouldn't any different from themselves."
But are they capable of carrying the Cardinals deep into the postseason? Let’s take a look.
Shelby Miller wasn’t just one of the top rookie pitchers during the first half of the season, he was one of the top pitchers in the game. Over his first 18 starts, the 22-year-old posted a 2.92 ERA and .225 opponent batting average with 112 strikeouts in 104.2 innings.
The Cardinals wisely offered Miller additional rest surrounding the All-Star break after he showed signs of wearing down in late June and into July. Although he had an up-and-down second half, the right-hander completed the final month of his first full season in the major leagues on a positive note by going 3-0 with a 2.76 ERA over five starts.
However, facing the Pirates has been an ongoing nightmare for Miller.
In four starts against them during the regular season, Miller went 0-4 with a 5.32 ERA, .319 opponent batting average and 21/9 strikeout-to-walk ratio in 22 innings. In fact, each start was progressively worse.
In his third outing of the season, on April 17, Miller was saddled with the first loss of his big league career despite allowing two earned runs on six hits and a walk with six strikeouts over six innings.
He ran into Pittsburgh again at the end of the month and didn’t fare any better, picking up his second loss of the year. Lasting only 5.2 innings, Miller allowed three earned runs on seven hits and three walks while striking out seven batters.
Miller’s third loss against the Pirates came on August 14, exactly one week after he was struck by a line drive on his right elbow and forced to leave his start after only two pitches. Needing 112 pitches (72 strikes) to complete six innings, the right-hander allowed five runs (three earned) on eight hits and two walks.
Pittsburgh hammered the 22-year-old once again on August 30, as Miller surrendered five earned runs on eight hits and three walks over 4.1 innings.
So what has made the Pirates so successful against Miller?
For starters, they are a team that punishes fastballs. According to FanGraphs.com, the Pirates posted a 48.6 wFB—the fifth-highest total of all teams—during the regular season, meaning they generated 48.6 runs above average against fastballs. Combine that with the fact that Miller is a pitcher who relies heavily on his fastball, throwing it 74.1 percent of the time to be exact, and we have a recipe for offense.
Of the 20 home runs allowed by Miller during the regular season, six came against the Pirates. And wouldn’t you know, each was off of his fastball:
April 28: With a 1-2 count, Russell Martin homers to left center on an elevated 95 mph fastball.
April 28: With a 2-2 count, Jose Tabata jumps the yard to the opposite field on a 94 mph fastball.
August 14: With an 0-1 count, Pedro Alvarez got every bit of a middle-away 95 mph fastball, launching it 434 feet to straightaway center field.
August 14: Leading off the second inning, Garrett Jones ropes a line drive over the right field wall on a center-cut 95 mph fastball.
August 30: With an 0-2 count, Garrett Jones turns on a 92 mph fastball down the middle of the plate.
August 30: Russell Martin followed Jones’ blast with one of his own on the next pitch, an elevated 90 mph fastball at the top of the strike zone.
Miller’s fastball command will need to be sharp for him to be successful against Pittsburgh in the NLDS (and beyond). If he can establish the pitch throughout the strike zone early in the game, then he should at least have the opportunity to change speeds more often as the lineup turns over for a second and third time.
At the same time, given the Pirates’ track record against the 22-year-old, it wouldn’t be surprising to see Yadier Molina call more secondary offerings in the early innings.
Michael Wacha made it clear that he wouldn’t be long for the minor leagues this season after an excellent showing during spring training. The 22-year-old made his big league debut against the Kansas City Royals on May 30, allowing one earned run on two hits with six strikeouts over seven outstanding innings.
While Wacha bounced between Triple-A and the majors over the next month, he was called up for good by mid-August and quickly became another weapon in the Cardinals bullpen. Appearing in six games as a reliever, the right-hander posted a 2.53 ERA with 19 strikeouts in 10.2 innings.
As a result of Wacha’s overwhelming success, the Cardinals inserted him back into the starting rotation for the final month of the season. Along with fellow right-handers Adam Wainwright and Lance Lynn, he played a major role in the team’s remarkable 19-8 September record and NL Central Division title. Making five starts, Wacha was 2-1 with a 1.72 ERA, .198 opponent batting average and 28/10 strikeout-to-walk ratio in 31.1 innings.
Wacha also ended his impressive rookie campaign in spectacular fashion, coming within one out of a no-hitter before allowing an infield single to Ryan Zimmerman. The right-hander threw 112 pitches (77 strikes) in the outing, walking two batters and tallying a career-high nine strikeouts.
Unlike fellow rookie Shelby Miller, Wacha was successful against the Pirates during the regular season. Entering the game in relief of Miller on August 14, he tossed two perfect innings with four strikeouts.
Wacha made his only start against Pittsburgh on September 8 and picked up the win thanks to seven shutout innings of two-hit ball. He walked and struck out a pair of hitters in the outing.
Despite Miller’s overall body of work in what has been an impressive season—one that should result in a top-five finish in the NL Rookie of the Year voting—his ongoing struggles against the Pirates are a legitimate concern.
That being said, he’s proven to be reliable over the course of the season and, more importantly, capable of keeping the Cardinals in an important game even when he’s not at his best. However, in a five- or seven-game playoff series, I would play the hot hand and tab Wacha as the Cardinals' third starter following Adam Wainwright and Lance Lynn, respectively.
Which rookie right-hander will have a better postseason for the St. Louis Cardinals?
Besides his obvious late-season success, Wacha and catcher Yadier Molina have already executed a successful game plan against the Pirates on two separate occasions. The right-hander also neutralized their left-handed hitters, holding them to a .059 batting average (1-for-17). Miller, on the other hand, was hammered by the Pirates lefties this season to the tune of a .438 batting average (14-for-32) with eight extra-base hits.
While the Cardinals' success will depend on the performances of their veteran starters, the depth provided by Miller and Wacha at the back end of their postseason rotation should give the team a chance to play deep into October.
*Did you know that TBS is live-streaming playoff games this October? Click here for more information.