The Fantasy Baseball Sherpa

With fantasy baseball playoffs starting this week in many Head-to-Head leagues, your selection of Starting Pitchers takes on added importance.  Sure, you’re going to start Zack Greinke, Roy Halladay, and Tim Lincecum (assuming he’s healthy) if you’re fortunate enough to have them on your team this season.  But what if you’re trying to decide between Bronson Arroyo and Kevin Correia for your last pitching spot?

 You could “go with your gut” and hope for the best (good luck with that).  You could look up each pitcher’s historical record (assuming he has one) against his upcoming opponent(s) and use that as a guide, ignoring the fact that a team’s roster is likely to experience significant turnover from season to season that will render historical results obsolete.  You could rely on the Remainder-of-Season Forecasts in the Fantasy Baseball Sherpa’s In-season Updates (shameless self-promotion).

While the third option is definitely better than the first two, it still leaves out one crucial component if you’re trying to make a short-term decision on which pitcher to start:  the quality of the pitcher’s opponent.  How can this be quantified?  The same way you would quantify the pitcher’s results - look at the historical data.

To assess a starting pitcher’s upcoming matchup(s) we want to use opponents’ success (or lack thereof) against a specific team.  For example, if I play in a league that uses the standard 5 pitching categories (Wins, Saves, Ks, ERA, WHIP), I’ll want to look at MLB Opponent Pitching Stats in each category that involves starting pitchers, so that eliminates Saves from my list.

I want to set my scoring system up so that the least desirable opponents have the highest scores, and the most desirable opponents have the lowest scores.  The least desirable opponent would have the highest number of Wins (equivalently, the lowest number of losses), the biggest difference between AB and Strikeouts (or, if you prefer, the lowest Strikeout per AB rate), the highest number of Runs Scored (using this as a proxy for ERA), and the highest number of Walks + Hits (using this as a proxy for WHIP).  Conversely, the most desirable opponent would have the lowest number of Wins (equivalently, the highest number of losses), the highest Strikeout per AB rate, the lowest number of Runs Scored, and the lowest number of Walks + Hits.

We can set up a scoring system for which the “best” team in each category receives a score of 1.00, and all other teams receive a score between 0 and 1 depending on the ratio of their result to the result of the best team in each category.  Thus, the maximum score is the number of pitching categories under consideration (4 in my example).  Add up a team’s results in each category to get its overall score; again, the lower the overall score, the more desirable the opponent.

Based on games through 9/12/09, here’s how the 30 MLB teams rank using the 4 categories in my example (with their accompanying score):

1. Pit 2.82 (max score is 4.00)
2. KC 2.90
3. Cin 2.94
4. SD 2.95
5. Was 2.96
6. SF 3.05
7. Sea 3.06
8. Ari 3.08
9. NYM 3.08
10. Hou 3.09
11. Bal 3.10
12. Oak 3.12
13. ChC 3.15
14. Mil 3.17
15. Cle 3.19
16. CWS 3.20
17. Det 3.20
18. Atl 3.25
19. Tor 3.25
20. TB 3.29
21. Min 3.30
22. StL 3.33
23. Fla 3.35
24. Phi 3.38
25. Col 3.41
26. Bos 3.48
27. LAD 3.50
28. Tex 3.56
29. LAA 3.62
30. NYY 3.80

You may wonder about the impact of September call-ups on these rankings.  Generally, the teams with the highest scores (i.e. - those closest to 4.00) are fighting for playoff berths and figure to play their everyday lineups at least until they’re locked into a playoff spot.  Those with the lowest scores are generally calling up more minor leaguers and “seeing what they’ve got”, so it may be even more advantageous than this chart would indicate to stream pitchers facing these lower-ranked teams.

The approach I’ve outlined above can take some of the guesswork out of selecting starting pitchers for your weekly lineups.  Of course, use your common sense - given the choice, I’d much rather start Roy Halladay against the Yankees than start Jeff Suppan against the Pirates.  However, if you’re deciding among several pitchers of similar quality, this analysis can be extremely useful.

Good luck in the homestretch!

The Sherpa

Fantasy Baseball Sherpa

The Fantasy Baseball Sherpa’s Blog

@fantasy_sherpa on Twitter