Based upon my last article, I feel the Cardinals could make a strong approach to the “modern bullpen approach”.
In this article, I will discuss the difference between players who will pitch to start an inning, and the players who will pitch when there are runners on base, based upon quality of contact.
Thanks to the people at Statcast, there is a measure for this, called expected weighted on base average(xwOBA).
xwOBA measures the wOBA of a given player, along with their exit velocity and launch angle, giving more points to players who make outs, but hit the ball hard and at an optimal launch angle.
The pitching side of xwOBA is how well the pitcher prevents solid contact, along with their opponent’s wOBA.
I looked at the Cards’ pitching staff in terms of xwOBA, and how might each pitcher be useful in a given situation.
I looked at three factors, xwOBA with nobody on, xwOBA with runners on base/RISP, and situational xwOBA, where the tying or go-ahead run is at the plate or on the bases.
The data, from Baseball Savant, is what I measured over the previous 2 seasons(a minimum of 50 results).
As well as that, I only looked at pitchers who are currently on the 40-man roster, and added Juan Nicasio and Wade Davis(since I believe the Cards should sign the two in my other article).
I then took the difference of the xwOBA of nobody on from runners on base, and the difference of the xwOBA of runners on base from situational xwOBA to further determine a separation between the factors, as well as an average of the three.
Looking at this set of data, I then again classify these pitchers in groups based upon their quality of contact.
First, I grouped pitchers in a class called “Openers”, or pitchers who could start the game(thus xwOBA with no runners on base comes into play), or pitchers who are effective with no runners on base.
The first group(Classified by xwOBA with nobody on base)
Brett Cecil- .271 xwOBA
John Brebbia- .292 xwOBA(though he could be effective late in the game as well)
John Gant- .311 xwOBA(effective late in game as well)
Luke Weaver- .315 xwOBA(also could be effective late in game as well)
Jack Flaherty- .325 xwOBA
All would be effective options for “The Opener” based upon quality of contact with no runners on base.
The second group are players who would be effective at getting the Cards out of a jam early in the game (1st through 6th innings).
The second group(classified with runners on base/RISP)
Tyler Lyons- .264 xwOBA
Sam Tuivailala- .275 xwOBA
Michael Wacha- .310 xwOBA(also a third group candidate)
Adam Wainwright- .310 xwOBA
The players can handle getting out of a jam early in the game, as well as starting the next inning.
The third and final group are pitchers who can be thrown in any situation at any time, and will throw the most innings on the team(top-tier pitchers based upon xwOBA).
League average xwOBA is .314, and these pitchers exceed that number remarkably.
The third group(denoted by average xwOBA),
Alex Reyes- .219 xwOBA
Wade Davis- .264 xwOBA
Juan Nicasio- .282 xwOBA
Matt Bowman- .285 xwOBA
Carlos Martinez- .286 xwOBA
The Cardinals, with a few additions, have the staff to implement this approach.
However, improving the defense is another task that needs to be addressed so these pitchers can attain more likely success.