Quick, think to yourself: Who do you predict will be the most effective St. Louis Cardinals starter in 2017?
Carlos Martinez seems like a safe pick: he was almost unanimously considered the Cardinals' ace in 2016 and arguably was the team's most effective pitcher in 2015, his first full season as an MLB starter, as well. Adam Wainwright had, by any measure, a down season in 2016, but he did somewhat dramatically under-perform his peripheral statistics while coming back from a de facto full season missed with injury; he also did this in 2012, and in 2013 he won the National League Cy Young Award For Guys Not Named Clayton Kershaw Because Come On Now This Isn't A Fair Competition.
Lance Lynn was among the team's top starters in 2014 and for much of 2015 and depending on his Tommy John recovery, he could bounce back to that level again. Luke Weaver, and to an even greater extent Alex Reyes, are unproven commodities but exhibited flashes of their undeniable upside in their MLB debuts last season.
And then there's Mike Leake, the most boring pitcher among the top half-dozen Cardinals pitchers. This isn't necessarily meant as a slam: he's probably not the guy you'd most fear will be a complete catastrophe (think 2011 Ryan Franklin or 2013 Mitchell Boggs, but as starters) either.
But Leake, entering his age 29 season, has now pitched seven full-ish seasons in the big leagues and while he has never really sunk below mediocre, he has also never really risen above slightly above average. And when a player is the most expensive pitching free agent signing in franchise history (as much a reflection on the franchise's fiscal conservatism and tendency to rely on homegrown pitchers as on Leake himself), it is easy to view average as unacceptable.
By earned run average, 2016 was Leake's worst season, with a 4.69 ERA. Increases in the run scoring environment meant that Leake wasn't a complete disaster in run suppression, relatively speaking, but at 0.5 Baseball Reference Wins Above Replacement, he was certainly not worth his $12 million salary, and he is seemingly working from behind on justifying the $63 million he is owed through 2020.
But by fielding-independent pitching, which measures a pitcher's walks, strikeouts, and home runs allowed, so as to remove factors which are heavily dependent on his defense producing behind him, Leake had a career-best 3.83 FIP. Leake wasn't a superstar, but he was considered above average, and at 2.6 FanGraphs WAR (the one which more heavily weighs FIP than ERA), he was worth an estimated $20.4 million.
The easy temptation would be to proclaim that Leake got unlucky. But entering 2016, Leake had a reputation (and a stat line) as a pitcher who outperformed his FIP, sporting a lower ERA in five of his six seasons.
The logic, generally, was that Leake survived not on high strikeout rates, which would improve his FIP disproportionately, but rather allowing relatively weak contact; indeed, his career SIERA (a statistic which is spiritually similar to FIP but also weighs a pitcher's opponent contact quality) is lower not only than his career FIP, but also lower than his career ERA.
But for practical purposes, Mike Leake is not operating in a vacuum. While he is somewhat in the mold of Dave Duncan-era Cardinals pitching reclamation projects such as Jeff Suppan, Woody Williams, or Jason Marquis, low strikeout pitchers who still managed to survive and often excel at the Major League level, Leake does not receive the benefit of pitching with a superb defense behind him.
For instance, on the vaunted 2004 Cardinals, with the exception of Whoever Was Playing In The Outfield With Jim Edmonds And Reggie Sanders (before Larry Walker arrived in August, the team alternated among So Taguchi, Roger Cedeno, John Mabry, Marlon Anderson, and Ray Lankford), the entire defense consisted of above average fielders, with Scott Rolen in particular being an elite one that year. In 2016, Cardinals starters depended on a defense whose best fielder (not counting Yadier Molina, who has minimal direct contribution to fielding balls in play), Kolten Wong, was sent down to Memphis during the season and was occasionally relegated to the outfield, because reasons.
Because of a weak defense, the Cardinals currently have an above-average need for pitchers to strike batters out. With a good defense, weak contact inducing pitchers can be something of a market inefficiency, as the value of a strikeout for that team is marginally less. But pitchers like Mike Leake are dependent on their surroundings.
His ERA would have likely been much better under even an average defense in 2016, but it is nevertheless a shortcoming, albeit not necessarily an impossible one to overcome, that Leake is unable to, to some degree, overcome the lackluster defense. While any pitcher would suffer without proper defensive support, a pitcher in Leake’s mold is more susceptible to what seems to be bad luck.
We don't generally think of baseball players as members of systems, in the way we do in sports where the "team" aspect is more direct, but Leake seems to have been the victim of a bad system for his talents in 2016. In the same way that Troy Aikman, a Pro Football Hall of Fame quarterback, was unable to thrive in college at the University of Oklahoma when the team around him was built to run the wishbone, an offense built around talented running quarterbacks (which Aikman, an all-time great thrower, was not), Leake may need a systematic adjustment to live up to his run-suppressing potential.
Unlike Aikman, who needed to transfer to UCLA, Leake doesn't necessarily need a change of scenery: he just needs the Cardinals to be better at defense. Leake is being paid what is essentially the salary of an average pitcher and average pitchers are not necessarily able to overcome the seven guys playing behind them. With that said, if he is able to become more strikeout-oriented (he had a run of this last season, but he is not likely to turn into Max Scherzer anytime soon) or if (more likely) the defense behind him improves, it would not be unreasonable to expect that Mike Leake’s results could improve disproportionately in 2017.