Examining the fourseam fastballs of the 2015 St. Louis Cardinals

One of the most interesting parts about analyzing pitching is that no two pitchers have exactly the same repertoire—ultimately providing an opportunity for intensive data collection (using websites like BrooksBaseball) followed by the interpretation of said data. Some pitchers rely on "hard" stuff while others utilize "offspeed" or "breaking" stuff. Though quality secondary offerings are very important for sustained success, the number one staple of most MLB pitchers' repertoires is the fourseam fastball—unless, of course, we are talking about Randy Choate, who has thrown a grand total of 13 fourseamers in his PITCHf/x career (aka since 2007).

Thus, how do the fourseam fastballs of the 2015 St. Louis Cardinals stack up against each other? Below, you will find an interactive chart looking at five specific categories: 1) Usage (%), 2) Velocity (MPH), 3) Whiffs/Swing (%), 4) Line Drives/Ball in Play (%), and 5) HR/(FB+LD) (%). The data, pulled from BrooksBaseball, starts from the 2007 season, so some pitchers (i.e. Adam Wainwright) have much bigger sample sizes than others (i.e. Sam Tuivailala).

via infogr.am (web version)

I posed a question on Twitter last night to get a gauge of my audience's thoughts on categories one through three (usage, velocity, whiffs/swing), and no one got all three categories correct. If I recall correctly, no one got even two of the three correct, either. Because of the results of this exercise, I figured the above chart could be serve as a valuable resource going into the 2015 season.

1) Usage

The two most common answers were Lance Lynn (52.17%) and Trevor Rosenthal (79.27%), and while both do throw a ton of fourseamers, Kevin Siegrist runs away with the highest usage at a staggering 85.27%. Of note, a contributing factor "against" Lynn in this category is the fact that he throws a decent amount of twoseamers/sinkers (21.88%) as well. Tuivailala came in third with 78.07%, but his sample size is especially small, consisting of only two big-league appearances. After a long minor league season, spanning multiple levels, Tui's fastball lacked the life we had seen from him while he was with Double-A Springfield.

Rounding out the top five, Jordan Walden was fourth with 73.36%, and Michael Wacha was fifth with 61.20%. On the other end of the spectrum, Wainwright used his fourseamer less than 10% of the time, but given the depth of his repertoire (i.e. sinker, cutter, curve), this isn't unexpected. While he may use the pitch only 9.26% of the time, it is a pretty good indicator of the kind of "stuff" he is going to have in any given outing. If he's painting corners and jamming hitters with it, he's usually able to set up his secondary pitches much better. Seriously, his fourseam fastball use is something to keep a close eye on, particularly with the question marks surrounding his overall health.

2) Velocity

The majority of responses on Twitter last night pegged El Gallo as having the fastest fourseamer, and those that did were correct. Carlos Martinez (98.19 MPH) barely edged out Rosenthal (98.08 MPH) and Walden (97.54 MPH) in this category. As a starting pitcher, there is reason to believe that Martinez will see a slight dip in velocity, but I expect him to use his sinker more frequently in 2015, meaning he should be able to conserve his fourseamer velocity for situations that call for a strikeout. Also, with the ink still fresh on his new contract extension, it will be intriguing to see if Lynn will be able to keep his fourseamer velocity up near 94 MPH. As I have written before, I am particularly fond of Lynn's fourseamer.

If he had thrown more fourseamers to qualify, Choate would take the "crown" for slowest fourseamer on the team (88.11%). However, a sample size of 13 is nowhere near enough, so the "winner" is Villanueva with 89.47 MPH. While Jaime Garcia, Marco Gonzales, and Tyler Lyons all hover around 90 MPH, the newly-acquired long-man is the only qualified Cardinals pitcher who averages under 90 MPH on his fourseamer. It really is okay, though, because the rest of his repertoire complements his fourseamer, and he finds a way to make it work.

3) Whiffs/Swing

Rosenthal led this category with a whiffs/swing of 28.78%. Lynn, armed with his "heavy" fastball, came in second with 25.05%, and Walden was third with 24.16%. Gonzales was lowest with 8.70%. While the consistency of his changeup makes his fourseamer appear faster to hitters, the 23-year-old lefty get the majority of his swings and misses from his changeup and breaking balls. Given its near-100-MPH velocity, Martinez's whiffs/swing was relatively low at 18.14%, but I firmly believe this will increase in 2015 as Martinez further develops his repertoire and adjusts his approach to pitching as a starter.

4) LD/BIP

The importance of line drives per ball in play is that it looks at quality of contact, and as we already know, line drives lead to hits way more often than ground balls and fly balls. Seth Maness (31.25%) and Gonzales (30.61%) find their names atop this category—a category in which pitchers don't really want to lead. However, even with a high LD/BIP%, Gonzales has held hitters to a .212 batting average and .091 ISO on the pitch. If his LD/BIP remains above 30%, one could reasonably expect hitters to have more fruitful results going forward. While Walden leads the staff (by at least three percentage points) with 19.38%, hitters have managed a .241 average and .130 ISO against his fourseamer.

5) HR/(FB+LD)

Again, Tuivailala needs to build a (much) larger sample size, but his 12.50% tied for the highest on the team with Maness, and as with LD/BIP, this is not a category a pitcher wants to lead. If Maness has one true "Achilles heel," it's the long ball, and here's to hoping he can curtail it in 2015. Martinez, who has allowed only five home runs total in two MLB seasons, leads the team with 3.66%, but as you can see, Gonzales (3.70%) and Rosenthal (4.38%) aren't too far behind.

Bottom line

While the Cardinals have a lot of effective fourseamers on staff, three pitchers stand out most (in this order): 1) Rosenthal, 2) Walden, and 3) Lynn. Siegrist has a good fourseamer as well, but he was so bad last season that I feel it's necessary to see another season before making a final decision on where the pitch ranks on the team. Based on velocity alone, Martinez is worth of being in the top three, but until he induces more swings and misses, he falls just outside. Yet, his ability to repel home runs has been especially impressive two years into his career, and that goes beyond just the "for what it's worth" category. With time, Tuivailala might find himself in the top three as well, but he needs some Triple-A seasoning before we can really include him in the conversation. All things considered, though, Rosenthal has the very best fourseamer on staff, and if he is able is able to make a few adjustments in 2015, hitters will stand no chance.

Who do you have in your top three regarding fourseam fastballs? Please include your answer in the comments section below.

Credit to BrooksBaseball for the data used in this post.