A pitcher who regularly gets an inning-ending double play may look especially good at escaping trouble. But the total alone does not tell you how much trouble he created—or how often the defense had a realistic chance to turn two.
For handicapping research, separate the opportunity, the batted ball and the conversion. A double play is the result of a sequence, not an independent pitching skill that can be read directly from one season total.
Define what you are counting
A defensive double-play total includes more than ground-ball double plays. A line drive followed by a throw to a base can also produce two outs. If your question is whether a pitcher can induce a useful ground ball, do not combine every kind of double play into the answer.
For a simple review sheet, label a standard ground-ball opportunity as a plate appearance beginning with a runner on first and fewer than two outs. That is a screening definition, not a guarantee that any particular ground ball can become two outs. Use the same definition for every pitcher you compare.
A hypothetical example
Suppose Pitcher A's defense turns 12 ground-ball double plays in 60 qualifying plate appearances. Pitcher B's defense turns eight in 25. The raw count favors A, but the conversion per screened opportunity is 20% for A and 32% for B.
Those figures do not prove B is the better pitcher or that he will repeat 32%. They show why the denominator changes the question. A may simply have supplied many more opportunities by allowing additional baserunners.
Then examine the actual ground balls
Within the screened situations, record how often the batter puts a ball on the ground. After that, consider where it goes, how quickly the fielders can get to it and whether a second out is realistic.
A hard ball directly to an infielder, a slow roller requiring a long charge and a ball that pulls the fielder away from the base do not present the same play. A pitcher-level summary can conceal these differences.
Attach the people and the situation
The batter's speed and the runners' movement affect the play. So do the middle infielders, the first baseman and the actual defensive alignment. A rotation change behind the pitcher can change the group executing the sequence even if the pitcher is unchanged.
Also retain the outs and score. With a run threatening to score, a defense may prioritize an out at home or the safest single out. A missed opportunity to turn two is not automatically an error or a poor decision.
Do not turn an escape into a run-prevention model
Allowing fewer baserunners can be more useful than repeatedly needing a double play. Keep walks, hits and strikeouts in the broader review instead of rewarding the rescue while ignoring the situation that made it necessary.
A short postseason sample is particularly limited. One well-placed ground ball can reshape an inning and the final score without establishing a stable rate.
A practical checklist
- Separate ground-ball double plays from all defensive double plays.
- State the opportunity definition and show the sample size.
- Review ground-ball creation before defensive conversion.
- Check the current infield, batter speed and game situation.
- Compare the escapes with the baserunners allowed.
The goal is a more accurate description of how innings ended—not an automatic wager, a guaranteed escape or a reason to ignore the current price.
Definitions
See MLB's double-play definition and ground-into-double-play definition. The example and screening calculation above are hypothetical educational tools, not a published MLB ranking.
