Deciding Among Starting Pitchers (6/21/09)
Monday, June 22nd, 2009So, it’s Sunday night or Monday morning, and your league’s weekly lineup submissions are due. You’re trying to decide among three starting pitchers (whether on your current roster or not) to fill your last pitching slot. How should you go about it?
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 6/20/09, here’s how the 30 MLB teams rank using the 4 categories in my example (with their accompanying score):
- SD 2.96 (max score is 4.00)
- Was 2.98
- KC 3.03
- ChC 3.07
- Oak 3.13
- SF 3.13
- CWS 3.15
- Sea 3.15
- Ari 3.18
- Hou 3.18
- Atl 3.20
- Cin 3.21
- Pit 3.22
- Bal 3.34
- Tex 3.35
- Fla 3.36
- NYM 3.39
- Mil 3.40
- StL 3.41
- Det 3.42
- LAA 3.43
- Col 3.43
- Cle 3.46
- Phi 3.50
- Min 3.53
- Bos 3.69
- NYY 3.70
- TB 3.71
- Tor 3.72
- LAD 3.81
No surprise to see teams like the Nationals, Royals, Padres, A’s, Mariners, and Giants at the top of the list of most desirable opponents, but the presence of the Cubs among the “worst” offensive teams is a bit of a surprise to me. If you’d asked me before the season started, I would have told you that the Cubs should have one of the best offenses in baseball. Of course, Aramis Ramirez’ injury combined with slow starts by Geovany Soto, Derrek Lee, and Alfonso Soriano have all contributed to the Cubs’ abysmal ranking. However, it points out the need to take a quick glance at a team’s current overall health compared to its health season-to-date. The NY Mets are ranked in the middle of the pack according to this chart, but sans Carlos Delgado and Jose Reyes, they’re obviously a less formidable foe now than they would be if this pair were healthy. Tracking the standings over time (I’d suggest weekly or bi-weekly updates) will give you a good sense of which team’s offenses are improving, treading water, or getting worse.
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 Johan Santana against the Dodgers than start Livan Hernandez or Tim Redding against the Padres. However, if you’re deciding among several pitchers of similar quality, this analysis can be extremely useful.
Until next time!
The Sherpa
The Fantasy Baseball Sherpa’s Blog