Roster Surplus and Depth Questions

The 2018 Milwaukee Brewers are in quite a strange position, representing the bundle of contradictions that defined their uncanny 2017 campaign. On the one hand, the organization dropped a “rebuilding” narrative in 2015, meaning that industry writers, analysts, and fans alike did not expect the club to compete, let alone contend, for several years; on the other hand, the organization built a flexible, aggressive team with a fantastic pitching staff that could capitalize on a mediocre league. In the first case, 2017 is an unadulterated success, while the latter case leads one to question how the team could have improved to reach the playoffs.

Those narratives will undoubtedly carry into 2018 guided by the very same contradictions: Milwaukee will indeed be developing many young players at the MLB level (including Lewis Brinson, Josh Hader, Brett Phillips, and Brandon Woodruff), while the team also has several opportunities to improve with established players (either through trades involving their prospects, through free agency signings, or both).

To put it another way: GM David Stearns can take the roster in several directions, and certainly has the resources available to contend while continuing to develop some players.


One way to assess player value, and therefore roster needs, is to estimate the surplus value that each player (and their contractual situation) provides the team. Value is assumed to be production and scarcity, recognizing that a player is not simply valuable to a club based on production, but also based on cost and the general availability of that skill set within the MLB. Surplus is the difference provided between a player’s production and their contract, recognizing that these aspects can be double-counted (a team simultaneously receives a player’s production on the field and their production gauged against their contract). Based on these assumptions, I tracked the surplus value of the Brewers 40-man roster (as of October 20, 2017) by using harsh depreciation to reduce each player’s maximum value (recognizing that a player’s performance typically declines over time save for rare cases).

The following chart tracks changes in surplus entering 2017 to entering 2018, while also assigning an Overall Future Potential (OFP) role for each Brewers roster member:

Player Surplus_18 Surplus_17 Surplus_OFP Mix 18-17 Role-18
Jonathan Villar $41.6 $54.6 $19.5 $38.6 -$13.1 -$22.1
Ryan Braun $22.3 $35.0 $48.9 $35.4 -$12.7 $26.6
Travis Shaw $42.9 $18.7 $34.2 $31.9 $24.2 -$8.7
Neil Walker $41.4 $15.5 $34.2 $30.4 $25.8 -$7.2
Zach Davies $39.9 $22.4 $19.5 $27.2 $17.5 -$20.4
Corey Knebel $21.2 $7.3 $48.9 $25.8 $14.0 $27.7
Domingo Santana $31.9 $8.9 $34.2 $25.0 $23.0 $2.3
Orlando Arcia $23.8 $1.8 $48.9 $24.8 $22.0 $25.1
Josh Hader $7.2 $0.0 $48.9 $18.7 $7.2 $41.7
Lewis Brinson -$3.4 $0.0 $48.9 $15.2 -$3.4 $52.3
Jimmy Nelson $23.4 $1.6 $19.5 $14.8 $21.9 -$3.9
Keon Broxton $19.8 $13.7 $1.4 $11.6 $6.0 -$18.4
Manny Pina $13.9 $1.2 $19.5 $11.5 $12.7 $5.6
Brett Phillips $12.7 $0.0 $19.5 $10.7 $12.7 $6.8
Anthony Swarzak $10.8 -$1.9 $19.5 $9.4 $12.7 $8.7
Jared Hughes $2.8 $5.3 $19.5 $9.2 -$2.5 $16.7
Jeremy Jeffress $3.3 $22.7 $1.4 $9.1 -$19.4 -$1.9
Stephen Vogt $6.3 $16.3 $1.4 $8.0 -$10.0 -$4.9
Hernan Perez $13.6 $8.9 $1.4 $8.0 $4.7 -$12.2
Eric Sogard $11.0 $10.3 $1.4 $7.6 $0.8 -$9.6
Junior Guerra $5.2 $16.1 $1.4 $7.6 -$10.9 -$3.8
Taylor Jungmann $10.0 $10.0 $0.1 $6.7 $0.0 -$9.9
Jacob Barnes $12.7 $4.2 $1.4 $6.1 $8.5 -$11.3
Carlos Torres $1.1 $15.8 $1.4 $6.1 -$14.7 $0.3
Andrew Susac $3.0 $9.4 $1.4 $4.6 -$6.4 -$1.6
Chase Anderson $5.0 -$13.1 $19.5 $3.8 $18.2 $14.5
Jett Bandy $3.3 $6.6 $1.4 $3.8 -$3.3 -$1.9
Oliver Drake $5.5 $2.8 $0.1 $2.8 $2.7 -$5.4
Eric Thames $4.7 -$16.0 $19.5 $2.7 $20.7 $14.8
Aaron Wilkerson $4.1 $0.0 $0.1 $1.4 $4.1 -$4.0
Jesus Aguilar $7.6 -$5.1 $1.4 $1.3 $12.8 -$6.2
Taylor Williams -$0.1 $0.0 $1.4 $0.4 -$0.1 $1.5
Adrian Houser $0.6 $0.6 $0.1 $0.4 $0.0 -$0.5
Jorge Lopez -$0.4 $0.2 $1.4 $0.4 -$0.6 $1.8
Brandon Woodruff -$0.5 $0.0 $1.4 $0.3 -$0.5 $1.9
Tyler Webb $0.1 $0.0 $0.1 $0.1 $0.1 $0.0
Wei-Chung Wang -$0.7 -$2.5 $0.1 -$1.0 $1.8 $0.8
Quintin Berry -$2.2 -$1.1 $0.1 -$1.1 -$1.0 $2.3
Brent Suter -$1.5 -$7.0 $1.4 -$2.3 $5.5 $2.9
Matt Garza -$11.4 -$12.5 $1.4 -$7.5 $1.1 $12.8

What these surplus numbers can suggest, in the abstract, is the difference between “the number of the wins above replacement” a player will produce during their contract and the OFP a team might receive if they traded the player at this point in time (alternately, they might suggest a contract range; for example, if the Brewers offered Neil Walker a $30 million contract, they would likely retain some surplus value during that contract).

Using the extremely interesting and difficult case of Jonathan Villar to interpret this table, his 2016 campaign and contract control years still loom large enough to suggest that the Brewers should not move the infielder for cheap; but the shortstop-turned-bench/utility option does mean that Villar’s ultimate role is trending downward, meaning that if Milwaukee believes that role decline is real and will continue to materialize, moving Villar for less than his top value could offset the issues of rostering a declining role. This should outline the difficulty of making roster decisions: in the case of Villar, there is not necessarily a right answer.

I should add that surplus value is abstract in the sense that there is a point at which additional surplus does not provide a team transaction value. Scooter Gennett and Chris Carter should be the most specific examples of this phenomenon in recent Brewers memory, as both players retained solidly positive surplus value entering 2017, but were essentially unwanted on the trade market and therefore expendable for nothing. Following this example, a rule of thumb might be to expect any type of roster move once a player’s surplus value dips below $20 million (or, less than three wins above replacement). Looking at the table of the Brewers roster above, this fact should seem intuitive with many of the names on the list (for example, it is highly unlikely that the Brewers would be able to move a player like Andrew Susac or even Eric Thames for their maximal surplus value).


By averaging each player’s 2017, 2018, and OFP surplus value, and comparing that to their change in value over time, a rather intuitive 2018 roster emerges. In this case, I excluded each player with a Negative-50 percent change in value (ex., a 50 percent decline), which produced need at Catcher, Second Base, and Right-Handed Pitcher, with additional question marks about the Utility roles. This is a rather succinct picture of the actual needs for the 2018 Brewers, and it also shows that if a few key free agents are retained, or similar free agents from outside the organizational signed, the Brewers can assemble quite a good roster:

2018 Player SurplusMix RoleTrend Change
UTIL Jonathan Villar $38.6 -$17.6 -45.6%
LF Ryan Braun $35.4 $7.0 19.7%
3B Travis Shaw $31.9 $7.7 24.3%
2B Neil Walker $30.4 $9.3 30.7%
RHP Zach Davies $27.2 -$1.4 -5.3%
RHP Corey Knebel $25.8 $20.8 80.7%
RF Domingo Santana $25.0 $12.6 50.6%
SS Orlando Arcia $24.8 $23.6 94.9%
LHP Josh Hader $18.7 $24.5 130.9%
CF Lewis Brinson $15.2 $24.5 161.3%
RHP Jimmy Nelson $14.8 $9.0 60.5%
Keon Broxton $11.6 -$6.2 -53.0%
C Manny Pina $11.5 $9.1 79.1%
CF Brett Phillips $10.7 $9.8 90.9%
RHP Anthony Swarzak $9.4 $10.7 113.5%
RHP Jared Hughes $9.2 $7.1 77.2%
Jeremy Jeffress $9.1 -$10.6 -116.5%
Stephen Vogt $8.0 -$7.5 -93.1%
UTIL Hernan Perez $8.0 -$3.7 -47.0%
Eric Sogard $7.6 -$4.4 -58.7%
Junior Guerra $7.6 -$7.3 -97.0%
Taylor Jungmann $6.7 -$5.0 -73.9%
RHP Jacob Barnes $6.1 -$1.4 -23.2%
Carlos Torres $6.1 -$7.2 -118.1%
Andrew Susac $4.6 -$4.0 -86.9%
RHP Chase Anderson $3.8 $16.3 428.8%
Jett Bandy $3.8 -$2.6 -69.3%
RHP Oliver Drake $2.8 -$1.3 -48.1%
1B Eric Thames $2.7 $17.8 647.4%
RHP Aaron Wilkerson $1.4 $0.0 3.6%
1B Jesus Aguilar $1.3 $3.3 251.8%
RHP Taylor Williams $0.4 $0.7 161.3%
Adrian Houser $0.4 -$0.2 -57.4%
RHP Jorge Lopez $0.4 $0.6 150.0%
RHP Brandon Woodruff $0.3 $0.7 230.8%
LHP Tyler Webb $0.1 $0.1 75.8%
Wei-Chung Wang -$1.0 $1.3 -126.0%
Quintin Berry -$1.1 $0.6 -58.0%
LHP Brent Suter -$2.3 $4.2 -178.4%
Matt Garza -$7.5 $7.0 -92.6%
C Major Need
RHP Major Need
2B Major Need
UTIL Question

These tables need not force an analyst to rely on numbers alone in order to validate roster decisions. Compare the following descriptions of potential role upgrades for the 2018 Brewers with those players’ statistical trends, and find nearly 20 roster spots (on the 40-Man) that can be upgraded for 2018:

Potential Role Upgrades Role Trend Top Role Low Role Current Trend
Jonathan Villar -$17.6 Starting Shortstop Quality Utility Toward low role
Neil Walker $9.3 n.a. n.a. Free Agent ($41.4M)
Jimmy Nelson $9.0 n.a. n.a. Injury
Keon Broxton -$6.2 Starting Centerfield Org Depth Toward low role
Jeremy Jeffress -$10.6 High Leverage Relief Org Depth Reclamation
Anthony Swarzak $10.7 n.a. n.a. Free Agent ($9.0M)
Stephen Vogt -$7.5 Platoon Catcher Bat-First Depth Toward low role
Hernan Perez -$3.7 Starting Second Base Quality Utility Toward low role
Eric Sogard -$4.4 n.a. n.a. Free Agent ($7.6M)
Junior Guerra -$7.3 Starting Pitcher Org Depth Toward low role
Taylor Jungmann -$5.0 Rotation Depth Org Depth Toward low role
Carlos Torres -$7.2 Relief Depth Relief Depth Steady
Andrew Susac -$4.0 Depth Catcher Org Depth Toward low role
Jett Bandy -$2.6 Depth Catcher Org Depth Toward low role
Adrian Houser -$0.2 n.a. n.a. Injury recovery
Wei-Chung Wang $1.3 Relief Depth Relief Depth Steady
Quintin Berry $0.6 Org Depth Org Depth Steady
Matt Garza $7.0 n.a. n.a. Free Agent (-$11.4M)

The benefit of this exercise is that additional roster functions can be analyzed, either through descriptive or analytical means. For example, one could compare some of the best Rule 5 Draft Roster Protection candidates with the players above in order to find the most salient moves for the future value of the organization. Via

Player Top Role Low Role
Mauricio Dubon Second Division Starter Quality Infield Depth
Jacob Nottingham Catcher With Power Org Depth
Freddy Peralta Middle+ Starting Pitcher Quality Reliever
Marcos Diplan Pop-Up Pitcher Quality Reliever
Devin Williams Middle+ Starting Pitcher Injury Recovery

Once again, this should exhibit a rather intuitive process of evaluation. If the future value of a catcher such as Jacob Nottingham is better than either Stephen Vogt, Andrew Susac, or Jett Bandy (or all three players), it should not hurt to lose one of those players in order to roster Nottingham. Each of these catchers are good candidates for contractual non-tenders for this reason (and, indeed, catcher is a position that the Brewers can upgrade in terms of depth behind/alongside Manny Pina). Similarly, allowing Matt Garza to walk via free agency and rostering Marcos Diplan, Freddy Peralta, or Devin Williams in that place should improve the pitching surplus of the roster. Where it gets more interesting is considering a player like Mauricio Dubon, and whether he simply takes the spot of free agent Eric Sogard, or overtakes Villar or Hernan Perez.


Using these analytical approaches should validate the fact that the Brewers are in a unique position entering 2018. They are a good team, indeed, that also features many up-and-coming players to develop at the MLB level and many declining roles that can be replaced. Where surplus value becomes useful is targeting particular trades, or simply determining when a player should be released or non-tendered.

A player like Keon Broxton, Perez, Susac, or Vogt should demonstrate this difficult decision-making process, and perhaps cause fans to realign their expectations that these types of players can receive impactful trade returns to Milwaukee. Given the packed outfield for 2018, the Brewers could conceivably release a player like Broxton should trade partners refuse to bite with a 45-to-50 OFP / quality depth trade (matching Broxton’s $11.5M-to-$19.8M surplus), for the trouble is that Broxton’s expected role is indeed declining (and any particular trade partner will also know that). This should not simply be viewed as picking on Broxton, as the point exists for Vogt and several other players on the roster.

“Slingin’ Stearns” earned his nickname for wheeling-and-dealing on the trade market during his first offseason in Milwaukee, but that reputation has calmed over time (not surprisingly, as the club completed their rebuilding process). Stearns did not show any hesitation in aggressively using waiver claims and releases to define his 2016-2017 offseason, and now the GM’s reputation may be defined by how effectively he clears roster space for what’s next: refined future development and improved MLB roles to contend in 2018.

The 2017 season proved that these goals can align and coexist within the same roster, so there are no excuses for failing to improve this strategy by learning from the 2017 progression.

Photo Credit: Jim Young, USAToday Sports Images.


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