Stop the presses: I made a prospect list (or 2)

Top prospect lists are more of a form of art than a science, since they use observational rather than numerical data as an input. There are several prospect lists out there, so is there a need for another?

I have been trying to devise a way to evaluate prospects objectively, without gut feeling rankings that once made Tod Van Poppel the best prospect in baseball. Also, I strongly believe that starting pitching, relief pitching and position playing are different beasts, so lists that contain all 3 of them are mixing apples and oranges and tangerines. So, let's talk about oranges and tangerines and leave the apples for another day.

I created a preliminary formula mid-season, taking a cut in rating the Twins prospects after 2007. I knew that it was rough and extremely preliminary. Since, I devised the PE measurement, components of which were in the pitching evaluating formula and I think that this one is a bit more accurate, so I am willing to share with a bit more confidence.

The formula I use to evaluate Minor league pitching prospects is containing the following criteria

  1. Overall effectiveness compared to the average MLB starter or reliever

  2. Effectiveness improvement each of the last 2 years compared to the previous year

  3. level of play (i.e. AAA, AA, A etc)

  4. number of levels ascended

  5. Age

The formula is:

Where PE is pitching efficiency this year, the MLB average PE is the average starter or reliever PE in the majors in 2008, depending on whether the prospect is a reliever (def: more games in relief than started) or a starter, the level is the highest level the player played that year described by as follows: Rk (DSL/GCL) 1, Rk (APP) 1.5, A 2, A+ 2.5, AA 3, AAA 4, MLB 5, and the levels ascended is the difference of the highest level played from the lowest level played the last 3 years (using the former numbers) + 1 (i.e. if a player started at A+ and assented to AAA, the levels ascended would be 4-2.5 = 1.5 + 1 = 2.5). The + 1 is there to avoid dividing by zero issues. Players that stay at the same level have level ascended = 1. Age is the age of the player in the beginning of a season. The effectiveness has a higher weight than improvement and improvement between this season and the last has a higher weight than improvement between last season and the season before. In order to keep the integrity of the results, players who showed a negative improvement were scored as 0; however negative effectiveness compared to MLB PE was scored as was.

Here is how the Twins' starting pitchers rank using this formula:

Daniel Osterbrock, 21, Rk (ELZ), 28.01

Pedro Guerra, 18, Rk (DSL), 14.18
Miguel Munoz, 19, Rk (GCL) 10.23
Adrian Salcedo, 17, Rk (DSL), 10.00

Eliecer Cardenas, 20 (Rk, DSL) 9.91
Ramon Acosta, 21, Rk (DSL) 8.70
Bobby Lanigan, 21, A, 7.99
Michael McCardell, 23, A, 7.53
David Bromberg, 20, A. 5.39

Anthony Swarzak, 22, AAA, 2.34
Tyler Robertson, 20, A+, 2.25
Shooter Hunt, 21, A, 2.23
Errol Simonitsch, 25, AA, 2.17 (released)
Angelo Sanchez, 19, Rk (GCL), 1.93
Martire Garcia, 18, Rk (GCL), 1.87
Michael Tarsi, 21, A, 1.60
Jeffrey Manship, 23, AA, 1.54
Kevin Mulvey, 23,AAA, 1.53
Cole Devries, 23, A+, 1.16
Philip Humber 25, AAA, 1.14

Brian Duensing, 25, AAA, 0.67
Ryan Mullins, 24, AA, 0.49
Steven Hirschfeld, 22, A, 0.41
Alex Burnett, 20, A+, 0.31
Yohan Pino, 24, AA, 0.26
Jay Rainville, 22, AA, 0.18

Daniel Berlind, 20, A, -0.19
Deolis Guerra, 19, A+, -0.46
Oswaldo Sosa, 22, AA, -0.95
Brian Kirwan, 20, A+, -0.96

Before the newly drafted class had a chance to make a dent I indicated that in my opinion, Pedro Guerra was the best arm in the Twins minor leagues, and that the DSL Twins have some of the best pitching prospects.Using these results, that statement proved to be pretty accurate. However, Dan Osterbrock who was drafted on the seventh round this year from University of Cinncinaty, put incredible numbers in Elizabethton (7-2, 13 GS, 75 IP, 104 K, 8 BB, 3.00 ERA, 1.04 WHIP) easily earning him the title of the best Twins starting pitching prospect.

Dan Osterbrock is a 6'3", 186 lbs, lefty from Cincinnati, OH. He has an 87-91 mph fastball with plus location and a great changeup, which is his out pitch. He needs to develop and improve his breaking pitches. Think of a lefty version of Kevin Slowey with a better change up and not as good breaking stuff. He helped lead Elizabethton to the best record in the Appalachian League.

The DSL wealth needs to be taken more seriously and the players need to be included in the prospect list pool; this is a fact.

As far as relievers go, here is the ranking:

Robert Delaney, 23, AA, 13.65

Jose Gonzalez, 18, Rk (DSL) 12.02
Andrei Lobanov, 18 Rk (GCL) 10.52
Leonardo Parra, 21, Rk (DSL), 10.42
Anthony Slama, 24, A+, 9.72
Michael Allen, 21, A+ 9.15
Edison Alvarez, 19, Rk (DSL) 8.07
Jose Mijares, 23, AA, 7.37

Curtis Leavitt, 21 Rk (Elz) 4.45
Joe Testa, 22, A+, 4.31
Bobby Korecky, 28, AAA 4.11
Matthew Williams, 21, A+. 4.09
David Martin, 22, A, 3.67
Steven Blevins, 21, A+, 3.14
Blair Erickson, 23, A+, 2.92
David Shinskie, 24, AA 2.85
Danny Rondon, 21, Rk (Elz) 2.69
Ben Julianel, 28, AA, 2.49
Renzo Reverol, 17, Rk (DSL) 2.25

Jose Lugo, 24, A+, 1.74
Santos Arias 21, A, 1.73
Matthew Fox, 25, A+, 1.28
Bradley Tippett, 20, A, 1.27
Kelvin Mota, 20, Rk (GCL) 1.17
Timothy Lahey, 26, AAA, 1.08
Carlos Gutierrez, 21, A+, 1.04

Charles Nolte, 22, A, 0.98
Spencer Steedley, 23, A+ 0.84
Ludovicus Van Mil, 23, A, 0.69
Thomas Wright, 20, Rk (Elz), 0.64
Mariano Gomez, 25, AAA, 0.55
Ricky Barrett, 27, AAA, 0.36
Frank Mata, 24, AA, 0.23
Armando Gabino, 24, AA, 0.07
Henry Reyes, 23, A+, 0.04
Jean Mijares, 20, Rk (GCL) 0.01

Bruce Pugh, 19, Rk (GCL) -0.06
Jay Sawatski, 26, AA, -0.18
Carlos Carrillo, 18, Rk (DSL), -0.27
Kyle Aselton 25, AA, -0.31
Chris Anderson 22, A, -0.72
Eddy Santana, 20, Rk (DSL) -0.83
Lesmir Vargas, 21, Rk (DSL), -0.84
Lee Martin, 22, Rk (Elz) -0.98
Michael Mopas, 20, Rk (GCL) -1.12 (released)
Danny Hernandez, 22, A+, -1.15

The ranking of the relievers indicates the the winner of the MiLB pitcher of the year award, Robert Delaney, is the best Twins' reliever prospect, which is not a surprise.

Back to the formula. Do I think it's perfect? Nope. But I think that if a pitcher has actualized a 12.48 K/9, 13 K/BB, and 1.04 WHIP season (Osterbrock) should be valued more and ranked higher than a pitcher who supposedly has better tools but has been regressing every year in his professional career (Deolis Guerra). Think of it as a car race: If a driver with a stock Chevy Impala beats a driver with a stock Ferrari Testarossa more kudos to him. The Ferrari guy needs to know how to use his car and until he proves so, he should not be taken seriously. And this is not a list of who is the most ready for the majors, but of who has the most potential based on actualized potential and improvement throughout his minor league career, factoring in his age and level of play.

Because people would like to see tidy lists, here is my list of the top 15 starting pitching prospects and the top 20 relief prospects.


  1. Daniel Osterbrock

  2. Pedro Guerra

  3. Miguel Munoz

  4. Adrian Salcedo

  5. Eliecer Cardenas

  6. Ramon Acosta

  7. Bobby Lanigan

  8. Michael McCardell

  9. David Bromberg

  10. Anthony Swarzak

  11. Tyler Robertson

  12. Shooter Hunt

  13. Errol Simonitsch

  14. Angelo Sanchez

  15. Martire Garcia


  1. Robert Delaney

  2. Jose Gonzalez

  3. Andrei Lobanov

  4. Leonardo Parra

  5. Anthony Slama

  6. Michael Allen

  7. Edison Alvarez

  8. Jose Mijares

  9. Curtis Leavitt

  10. Joe Testa

  11. Bobby Korecky

  12. Matthew Williams

  13. David Martin

  14. Steven Blevins

  15. Blair Erickson

  16. David Shinskie

  17. Danny Rondon

  18. Ben Julianel

  19. Renzo Reverol

  20. Jose Lugo

Now that I am done with the oranges and tangerines, next will take a look at the apples, but, alas, there are a lot of varieties of them, so they will need to be sorted out.

Something about pitching or why Kevin Slowey was more effective than Johan Santana

In order to evaluate position players more effectively, a couple of weeks ago I introduced a new statistic, bating and fielding efficiency (BFE). There are some established statistical measure that can tell you about a pitcher's performance, independent of the fielding of the team behind him. A couple of those are Fielding Independent Pitching (FIP) and eXpected Fielding Independent Pitching (xFIP) and Defense-Independent Component ERA (DICE). You can see the formulae for these measurement in this excellent Wikipedia article. I have 2 problems with these formulae:

  1. They use arbitrary numericals to factor and add to the statistical measurements within their equations (3, 13, 2, 3.2)

  2. For some strange reason, hits given are not included, but home runs are, factored by a huge 13-times factor

  3. Bases on balls are factored by 3, strikeouts are factored by 2

  4. Home runs are based mostly on a hitters capability and the park and not on the pitcher, whereas the defense does not have that much of a role for a hit.

Let's clarify the last point:
One of the statistics I will use to evaluate pitching is WHIP. Arguably, WHIP might be defense dependent, but how much?

Defense has 2 flavors:

a. accuracy - reflected by Errors. Errors do not count on WHIP, so that is out.

b. range - let’s use the plus minus system for this to understand the impact:

in 2008 the best defender in baseball as far as plus-minus goes was Chace Utley with a total score of 49 (i.e. he made 49 plays the average player does not make). He made a total of 803 plays (340 POs and 463 assists) even if we assume that all those +49 plays took a hit away (which is a stretch, because some of those were to get the lead runner in a double play or fielder’s choice, both of which do not take hits away from a pitcher’s WHIP).

49 is 6.1% of his total plays. If you divide that by 5 starting pitchers you get 1.2%.

So the best defender in baseball saved 1.2% of the hits for a particular starting pitcher (stretch). If you take the MLB average for 2008 pitchers 0.37 BB/Hits, 0.37 of a pitcher’s WHIP is a factor of BB and 0.73 a factor of hits. So the difference that the best ranging defender can potentially make on a pitcher’s WHIP is 0.88%

With examples:

Perkins’ WHIP in 2008 was 1.470, in that theoretical best case scenario would have been 1.457

Let’s go more extreme: here are the best plus minus numbers per position in 2008 (2B was Utley): 1B +24, 3B + 32, SS +23, LF +23, CF +32, P +16.
If you build a team with those people as defenders, the 0.88% difference above due to just Utley would become 2.8%

In other words, Perkins with the best defense in the MLB Universe of 2008 would have a WHIP of 1.429 instead of 1.470 (even with the best case scenario that all plus plays take hits away). Not much difference. Certainly not enough to discount the hits a pitcher gives as part of how effectively he pitches.

I created a new measurement, called Pitching Effectiveness (PE) which is simply: (K/9*K/BB)/WHIP. All these factors take into account how a pitcher is performing without extraneous factors. Here is a list of the 2008 MLB pitchers who pitched more than 20 innings and had a PE over 20, broken down by starters and relievers and sorted by decreasing PE (I included all Twins pitchers for comparison):


Dan Haren, AZ 39.13
Josh Beckett, BOS 37.83
Roy Halladay, TOR 37.81
Ervin Santana, LAA 35.79
CC Sabathia, MIL 34.08
Ricky Nolasco, FLA 31.68
Cliff Lee, CLE 30.84
Rich Harden, CHC 30.77
Kevin Slowey, MIN 30.67
Tim Lincecum, SF 28.29
Randy Johnson, AZ 26.85
Mike Musina, NYY 26.66
Cole Hamels, PHI 26.52
James Shields, TBR 23.23
Johan Santana, NYM 22.54
Javier Vasquez, CHW 21.46
Roy Oswalt, HOU 21.19
Scott Baker, MIN 20.98
Ben Sheets, MIL 20.97
Zack Greike, KCR 20.86
Jake Peavy, SD 20.50

Other Twins:

Boof Bonser: 13.44
Fransisco Liriano: 11.91
(Matt Garza 10.91)
Nick Blackburn: 8.09
Glenn Perkins: 5.69
(Livan Hernandez: 3.13)


Mariano Riviera, NYY 189.22
Jonathan Papelbon, BOS 101.06
Billy Wagner, NYM 57.94
Sergio Romo, SFG 51.05
Kerry Wood, CHC 49.00
Hong-Chih Kuo, LAD 48.76
Grand Balfour, TB 48.49
Trevor Hoffman, SD 45.02
Joe Nathan, MIN 44.89
Scott Eyre, PHI 43.89
Matt Thorton, CHW 41.92
Brian Fuentes, COL 39.87
Mike Adams, SD 38.14
Joey Devine, OAK 37.91
Tagashi Saito, LAD 36.16
Joakim Soria, KCR 35.56
Carlos Marmol, CHC 35.22
Frank Francisco, TEX 32.67
Octavio Dotel, CHW 32.43
Rafael Perez, CLE 32.16
Scott Linebrink CHW 32.00
Chad Qualls AZ, 31.91
Jonathan Broxton, LAD 31.87
Jose Valverde, HOU 31.71
Mike Gonzalez, ATL 31.14
Jon Raunch, AZ 28.83
Max Scherzer, AZ 27.06
Brad Lidge, PHI 25.61
Joba Chamberlain, NYY 25.50
Neal Cotts, CHC 25.10
Taylor Buchholz, COL 24.89
Wade Corey, LAD 23.65
Joe Nelson, FLA 23.01
JUan Cruz, AZ 22.52
Jeremy Affeldt, CIN 22.37
Damaso Marte, NYY 22.36
Ramon Troncoso, LAD 22.10
Edwar Ramirez, NYY 21.89
Jesse Carlson, TOR 20.91
Doug Brocail, HOU 20.90
Arthur Rhodes, FLA 20.45
Brandon Morrow, SEA 20.12
Manny Delcarmen, BOS 20.08

Other Twins:

(Pat Neshek: 31.64 less than 20 innings)
Dennys Reyes: 16.59
Craig Breslow: 13.59
Jesse Crain: 10.90
Matt Guerrier: 7.00
(Juan Rincon: 6.27)
(Brian Bass: 4.58)

The MLB averages for 2008 were:

MLB starter average WHIP 1.39
MLB starter average K/9 6.20
MLB starter average K/BB 2.06
MLB Starter average PE: 9.19

MLB reliever average WHIP 1.39
MLB reliever average K/9 7.80
MLB reliever average K/BB 1.94
MLB reliever average PE: 10.89

It is expected that relievers would have higher PE numbers than starters and they do. A couple of observations: Slowey and Baker were the best Twins starters. Slowey is among the pitching elite. BTW, for those who are lamenting the Delmon Young trade, Matt Garza's PE was 10.91, placing him as the 5th best potential Twins starter. Glenn Perkins is trailing the starting group and Nick Blackburn's numbers are below MLB average, making Perkins and potentially both expendable. Bonser should get another chance to make the rotation and Liriano's PE was hurt by his horrid first few starts.

The Twins need at least 2 relievers above 20 in 2009 now that they lost Neshek. Mijares could be there, but at least another right handed reliever would be welcomed. From the list of relievers here, Jeremy Affeldt (22.37), Doug Brocail (20.90), Juan Cruz (22.52), Brian Fuentes (39.89, probably a closer someplace other than the Twins), Trevor Hoffman (45.02, probably a closer someplace other than the Twins), Bobby Howry (23.40), Damaso Marte (22.36), Arthur Rhodes (20.45) and Kerry Wood (49.00, probably a closer someplace other than the Twins) are free agents; so are Kyle Farnsworth (16.55), Brandon Lyon (15.23), Will Ohman (15.74), Darren Oliver (15.62) and Russ Springer (17.26), all with PE higher than the remaining Twins. Given the facts that the Twins would probably like a right hander and some of the above players will sign as closers, the list gets smaller, but there are still more than a few potential targets remaining. Other than Guerrier, the remaining bullpen arms were above league average in 2008.

One last parting thought: The PE is a useful tool to identify future closers. I think that PE > 40 equals good closer material. From the above list:

Sergio Romo, SFG 51.05
Hong-Chih Kuo, LAD 48.76
Scott Eyre, PHI 43.89 and
Matt Thorton, CHW 41.92

show closer potential.