Evaluating projections may be useful as the trade deadline approaches
With both the starting rotation and batting lineup ravaged by injuries, the Astros find themselves in an uncertain position. What will happen over the remainder of the season? And the answer to that question involves projecting the answers to associated questions: which players will return to the lineup and when will they return?
In theory we should turn to rest of season (ROS) projections for help. Fangraphs has a sophisticated playoff odds model which is updated and run daily. The underlying player depth chart ROS projections also are continuously updated. Part of this process involves roster resources staff making judgements about the impact of injuries on the team’s depth chart.
Since teams and analysts often will use these projections to inform their decisions at the trade deadline, let’s turn to the projections with a focus on the Astros.
The Fangraphs Playoff Odds Model seems fairly comfortable with the Astros’ current position. The Astros have a 68% chance of winning the division and 93% odds of making the playoffs. That’s a pretty good outlook for a team experience so many injuries. The Astros odds are shown below.
Fangraphs Model
If the model indicates an area of concern, it’s the declining odds of clinching a Bye in the playoffs. The odds were over 50% a few weeks ago, but it has declined to 44%. The Astros’ probability of a Bye is basically the same as the Blue Jays (45%). The only AL team with higher odds of a bye is Detroit (64%). It’s worth noting that the Astros’ win percent over the rest of season is projected at 53.2%, which is lower than the first half win % and slightly lower than the Mariners’ ROS win percent.
A related article is Dan Symborski’s July 18 article entitled “Which teams have the most to gain at the Trade Deadline.” The article is an interesting exercise, particularly if you are interested in the trade deadline decision making of other teams. However, I will focus on the Astros right now. Keeping in mind that his ZIPS model is different from the Fangraphs model, Symborski gives the Astros the third highest division odds (82%) and playoff odds (96%) in the MLB. The Astros also have the second highest World Series odds (12.8%), behind only the Dodgers. Assuming a trade acquisition would increase the Astros WAR by 1 win, the Astros’ playoff odds don’t increase very much in percentage terms (1.6%)—18 other teams would benefit more from a trade. However, a 1 win trade acquisition would give the Astros the second highest percentage increase in World Series odds (4.2% increase).
If you are wondering how the injuries affect the Astros’ playoff odds, we have to turn to the Fangraphs Depth Chart ROS projections. 62 games remain in the season, and the roster resources staff apparently assume that uninjured everyday lineup players will start 59 games. The remaining games played give you an idea of assumed return time periods for injured players. A few selections:
Rest of Season
(Games, wRC+, WAR)
FG Depth Chart
This seems consistent with Pena and Paredes returning around the end of July or early August, with Meyers and Alvarez returning near the end of August or in early September. This involves a lot of uncertainty, but the injury return dates don’t seem unreasonable. Once the lineup progresses as more injured players return, the Astros’ wRC+ and WAR over the remainder of the season is projected to be fairly productive.
We can also review the ROS starting pitchers in the FG depth chart.
Fangraphs
The depth chart projects that Luis Garcia and Christian Javier will make three starts between them. The depth chart also assumes that the two returning pitchers will have 12 appearances out of the bullpen between them. Arrighetti is assumed to return earlier than Javier and Garcia and start 6 games. The projections view Valdez, Brown, and Walter as the above average starters in the rotation. The projection for McCullers seems optimistic to me. However, if Lance is unable to starter 11 games this year, Walter and Gordon would probably increase their expected number of starts.
In any event, these reviews of the ROS depth chart provides information on the projections which underlie the overall Astros Win % projections.