An early look at the AL West standings
Maybe we have enough games to take an early look at the AL West standings. It’s probably too early because division standings don’t mean much at this stage. But the AL West was predicted to be a tight race, and the prediction is true so far.
Fangraphs
The Mariners, playing well over the last 10 days, have taken a 2 game lead over the Astros. One-half game separates the Astros and Rangers. The Athletics, with a .500 record, are hanging around the division leaders. The Rangers’ W/L record is over-performing their Pythagorean Record (“pythag” or “pythagenpat”). The Rangers are -15 runs in run differential and the team’s record is 3 games higher than its Pythag (12-16). The Astros Win% is 1 game below its Pythagorean Record. Based on Pythag, the Mariners and Astros are practically tied for division lead (16-12 and 15-12).
The most surprising part of the division standings is the relative status of offense and pitching for the Astros, Rangers, and Mariners. Going into the season, most analysts expected the Rangers to have the best offense and the Mariners the best pitching. So far the Rangers have the division’s worst offense based on runs scored per game. The Astros have experienced troubles in scoring runs, but it’s still not as bad as the Rangers. The Mariners have scored the most runs per game. Among the three teams, the Mariners’ pitchers have allowed the most runs and the Astros have allowed the least runs per game. Most of us expected the Mariners to have an opposite orientation—stingy on runs allowed but struggle in scoring runs.
Playoff Odds
The Fangraphs playoff odds currently indicate that the Mariners have an advantage at winning the division, while the Astros and Rangers have similar approximate even odds of making the playoffs. The default FG odds are based on the Fangraphs depth chart projection. Fangraphs also provides odds based on a method which uses Fangraphs WAR projections.
Division Odds Fangraphs / FG WAR
Mariners 45% / 38%
Astros 24% / 32%
Rangers 24% / 28%
Playoff Odds Fangraphs / FG WAR
Mariners 75% / 65%
Astros 52% / 60%
Rangers 53% / 56%
The FG-WAR variant of the Fangraphs playoff odd calculator is new for this year, and apparently Fangraphs is monitoring it to determine if it produces more accurate results. The base Fangraphs calculation converts Steamer/ZIPS projections into Base Runs before running thousands of simulations. The FG-WAR method substitutes the projections of WAR into the Base Runs stage of the model (before the simulated seasons). As the article linked above states:
it’s not yet clear if there’s an advantage to using WAR for the initial projections instead of BaseRuns. The difference between the two is also not easily explained. These are two completely separate calculations. WAR includes numerous additional data points that the BaseRuns framework does not, such as park adjustments, league adjustments, fielding, catcher framing, context neutral linear weights, and FIP for pitcher calculations, just to name a few. But BaseRuns continues to be an accurate run estimator based on standard counting stats.
For whatever reason, the WAR version of the FG playoff odds are more favorable to the Astros than the Base Runs version. Both variants make the Mariners the current favorite to win the division, but the FG WAR version projects less separation between the Astros and Mariners for division winning odds. Furthermore, the Astros overall playoff odds move from 52% to 60% with the WAR version.
Setting aside the discussion of playoff odds mechanics, the pre-season story line that the AL West will be a tight dog fight among three teams (Mariners, Astros, Rangers) seems to be confirmed. I don’t see any obvious reasons to believe that this close battle will not continue down to the end. I should also mention that division battles between the three top teams and the A’s and Angels could be a deciding factor. The A’s have a strong offense and problematic pitching which could lead to total win percent ranging from 75 to 82 wins. A good team which isn’t well prepared might be susceptible to losing a series against Sacramento.
I’m sure we will also see regression on both offense and pitching by all three AL West leaders. Seattle’s pitching staff has tremendous talent and likely will get improved runs allowed results in the future. But the Mariners offense may be playing above its head at the moment. I doubt that both the Astros and Rangers will continue to perform so poorly at scoring runs. The Rangers are 29th in wRC+ with runners on base (71) and the Astros are 19th with runners on base (93). These type of stats tend to be volatile due to sample size, but they can explain currently poor RS/G marks, but often regress toward the mean over longer periods of time. Given the underlying offensive talent on both the Astros and Rangers, I would expect offensive improvement for both teams in the future.