Chapter 9 of 11
The intentional walk
Putting a man on base on purpose adds runs to the other side's ledger. Sometimes the hitter you avoid is worth it.
The short version
A walk is a gift unless the hitter you skip is far better than the one you get, or the extra force play buys you a win.
KBO 2026 season data through Oct 13, 2026
01
The idea
The intentional walk gives the offence a free baserunner in exchange for not pitching to one particular hitter. It buys two things: the chance to face someone worse, and a force play at every base, which makes a double play possible. It costs a runner, and runners are what runs are made of.
In the run expectancy table the cost is plain, and it is large. Whether the walk is worth it comes down to how much better the skipped hitter is than the next one — and to whether the extra runner even matters on the scoreboard.
02
The math
cost of the walk = RE(after walk) − RE(before); break-even gap ≈ cost × wOBA scale
The walk breaks even, roughly, when the wOBA gap between the two hitters times the plate appearances it affects covers the runs the walk adds. With one plate appearance at stake, the gap has to reach ΔRE × the wOBA scale (1.04 this season).
| Situation | Runs | Chance of a run | Win, tied bottom 9th | Break-even wOBA gap |
|---|---|---|---|---|
| →one out | +0.27 | +1.0 | +0.5 | .279 |
| →one out | +0.21 | −5.2 | −2.6 | .223 |
| →one out | +0.29 | +0.8 | +0.4 | .298 |
| →nobody out | +0.43 | +2.6 | +1.3 | .447 |
| →two out | +0.14 | +1.3 | +0.6 | .150 |
| →two out | +0.21 | +6.4 | +3.2 | .216 |
The classic walk — first base open, runner on second, one out — adds 0.27 runs to the other side's expectation. To make that up in one plate appearance, the hitter you skip would need to be about 279 points of wOBA better than the one you face instead. The gap between the league's best hitter and an average one is rarely half that.
Look at the win column, though. With a runner on third and one out in a tied bottom of the ninth, the walk changes the home side's win value by −2.6 points — it helps the defence: the runner on third is the only one who matters, and the walk adds a force and a double play. Loading the bases from second and third moves it by +0.4. That is where pitching around a dangerous hitter costs almost nothing, and where the gap between him and the next man decides the call.
03
This season in the KBO
Intentional walks
137
Per team game
0.10
Per game, 2003
0.12
Games per walk issued
10.5
KBO managers issued 137 intentional walks this season — one every 10.5 team games. It is a rare weapon, and the hitters it is used on are the ones you would expect.
| Most often walked on purpose | IBB | wOBA |
|---|---|---|
| Kim Do-yeong KIA | 11 | .463 |
| Victor Reyes Lotte | 9 | .421 |
| Austin Dean LG | 8 | .468 |
| Lewin Diaz Samsung | 5 | .401 |
| Choi Jeong SSG | 5 | .441 |
| Kang Baek-ho Hanwha | 5 | .393 |
League wOBA .346.
04
When the conventional wisdom is wrong
01
“Set up the double play”
With runner on second and one out, the walk adds 0.27 runs. A double play ends the inning, but a walk is guaranteed and the grounder is not; the trade loses in nearly every early-inning case.
02
The walk-off exception
When the runner on third is the winning run with fewer than two out, extra runners behind him are nearly free. Walk the great hitter, take the force, and pitch to the worse one.
03
Never with two out and first open, unless…
With two out the double play is gone, so the walk only adds a runner. It needs a gap of 150 points of wOBA to break even — the next hitter has to be dramatically worse.
04
Pitching around is not the same
Throwing careful strikes to a great hitter, and accepting the walk if it comes, keeps the chance he chases. The intentional walk gives up that chance entirely.
The break-even gap is a first-order estimate: it treats the skipped hitter's plate appearance as replaced by the next hitter's, in the same situation, and ignores the knock-on effect on who bats later in the inning. The tables assume league-average hitters on deck; the walk's real value depends on exactly who is coming up.