How do you research a stolen base prop?
Reaching base is the gate, so on-base percentage comes before sprint speed. Then attempt rate rather than raw steal totals, then the pitcher's time to the plate and how often he throws over, then the catcher. Speed only becomes the deciding factor once the chance exists at all.
Most stolen base content starts with sprint speed. It is the most visible input and the least useful place to begin, because it only decides anything once several other things have already gone right.
Before speed is relevant, four other things have to be true. He has to reach base. He has to be allowed to run. The pitcher has to give him a window. The situation has to permit it. Speed only decides the outcome once all four have already happened.
So work in the order the constraints actually bind.
First: does he get on base at all
This is the gate, and it is where most stolen base bets are lost before the game starts.
A runner cannot steal first. If a hitter reaches base once every three games, his speed is irrelevant to tonight’s prop, because the most likely outcome is that he never gets the chance.
On-base percentage, not batting average. A walk is a stolen base opportunity in exactly the way a single is, and the fastest players in baseball are often the ones with the weakest on-base skills, which is precisely the tension this market prices.
Lineup spot is the multiplier again. Leading off means more plate appearances and therefore more chances to reach.
Second: does he actually run
Attempt rate beats raw totals, and it is the single most useful reframing on this page.
A player with 30 steals might have attempted 34 times in 180 opportunities. Another with 12 steals might have gone 12 for 13 in 40 opportunities. The second has the higher conditional attempt rate when he reaches, and the raw steal column hides that completely. Which of them is the better bet tonight still depends on the price, the pitcher, the catcher and the game situation.
What you want is roughly: attempts divided by times on first with second base open. Where that is not available, attempts per time on base gets you most of the way.
The dugout is part of this. Some clubs run constantly and some almost never, and an individual’s green light is not entirely his own. A fast runner on a team that rarely runs gets fewer chances than his legs suggest.
Third: is the pitcher giving him a window
The pitcher’s delivery is a large part of what makes a steal possible, and it gets less attention than the catcher’s arm.
Time to the plate is the number. A right-hander at 1.3 seconds from the stretch is a different problem from one at 1.5, and two tenths of a second is a large share of the window a runner is working inside.
Left-handers face the runner, which changes the whole calculation. A lefty with a good pickoff move suppresses attempts before they happen, and the suppression shows up as nothing occurring, which is easy to miss when you are looking for a signal.
How often he throws over. Since 2023 there is a limit on disengagements per plate appearance, which means a pitcher who uses them early has fewer left, and runners know it.
Fourth: the catcher
Pop time, the interval from the catch to the ball arriving at second, is the number. Elite sits around 1.9 seconds and average closer to 2.0, and the Statcast pop time leaderboard has every catcher.
Worth checking, and worth keeping in context: a catcher with a strong arm behind a slow delivery still concedes bases, because the runner was gone before the ball arrived. The two work together rather than one overriding the other.
Sprint speed for the runner is on its own Statcast leaderboard.
Why pre-2023 numbers are stale
Three rule changes landed together and they all pushed the same way:
- Bigger bases, shortening the distance between first and second.
- A limit on pickoff attempts per plate appearance, so a runner who survives two disengagements has a much better third look.
- The pitch clock, which compresses the time a pitcher has to hold a runner.
Attempt rates and success rates both rose. Any base-rate figure you read that was published before 2023 is describing a different sport, and this is the market where that matters most.
Being straight about our own coverage
We price this market on the Lab board, and it is the thinnest research layer we have. Stolen bases are a low-frequency event on a board built mostly around hitting, and we have far fewer settled stolen base leans than we do hits or total bases.
So this page is a research path and a description of the market’s structure. It is not a claim that we have measured an edge here, because we have not.
Settlement
Caught stealing counts for nothing. The prop counts successful steals. A runner thrown out twice trying settles the same as one who never left first.
Defensive indifference is not a stolen base. Late in a game with the defence ahead and conceding the base rather than playing out of position, the scorer rules indifference and no steal is recorded. A real way an Over dies in a game that looked ideal for it.
On a double steal where one runner is thrown out, NOBODY gets a steal. MLB’s definition is explicit: a runner “is not given credit for a steal if he safely advances but another runner also attempting to steal on the same play is thrown out”. This is the settlement rule most likely to cost you a prop that looked like it landed.
Balks, wild pitches and passed balls advance the runner without a steal, unless he was already attempting to steal as the pitch got away, in which case he is generally credited. Advancing on a defensive error is never a steal.
Check your book, since these vary at the edges. DraftKings’ baseball rules are where we check.
The order to work in
- Will he be on base? On-base percentage, then lineup spot.
- Does he run, and will they let him? Attempt rate, not steal totals.
- Does the pitcher allow it? Time to the plate, handedness, disengagement habits.
- The catcher. Pop time, in proportion.
- The game script. A blowout invites indifference; a one-run game invites a real attempt.
Notice that sprint speed is not a separate step. It sits inside step two, where a player’s attempt rate and success rate already reflect it, and on its own it says nothing about whether tonight produces a chance at all.
Where to see today’s lines
Stolen base lines sit on the Lab board with the price beside them, and today’s MLB player props carries anything we selected.
The market with the same opportunity-first structure is how to research batter walk props: both are gated by reaching base and by someone else’s decision, rather than by the hitter’s bat.
What we are not claiming
No measured predictive value for any statistic here against a posted stolen base line, and no edge claim of any kind. Definitions come from Baseball Savant. Our own coverage of this market is thin and the page says so rather than dressing the gap up.
Quick answers
What matters most for a stolen base prop?
Whether he gets on base at all. A fast runner who reaches base twice a week cannot steal, and no amount of sprint speed fixes that. Opportunity comes before ability on this market.
Did the 2023 rule changes affect stolen bases?
Substantially. Bigger bases, a limit on pickoff attempts and the pitch clock all pushed attempt rates and success rates up together. Any figure quoted from before 2023 describes a different game.
Does a caught stealing count for a stolen base prop?
No. The prop counts successful steals only. A runner caught twice trying has zero for settlement purposes.
Does defensive indifference count as a stolen base?
No. If the scorer rules that the defence conceded the base rather than contested it, it is not recorded as a stolen base and does not count.
On a double steal, does the safe runner get a stolen base?
No. MLB's own definition says a runner is not credited with a steal if he advances safely while another runner attempting to steal on the same play is thrown out. Both attempts, one out, and neither is recorded as a stolen base.
Want tonight's board?
The Lab prices every player prop on the slate, shows the form and the matchup behind each line, and posts a short card before first pitch. Every pick is graded in public afterwards, win or lose. It is free and there is nothing to sign up for.