Last night, the Kansas City Royals laid down four sacrifice bunts, one fewer than they had in the entire month of September. It was a veritable bunt-a-palooza, with Ned Yost’s squad taking small ball to an entirely different level. Predictably, sabermetrically-inclined fans and analysts hated it, as the community has spent years preaching the value of not giving away outs. The live blog was inundated with angry Royals fans who wanted Yost fired, even as the team staged a miracle comeback, because he handed the A’s more than an innnings worth of free outs in his pursuit of runner advancement.

But let’s talk about all those bunts, and whether they were actually harmful to the Royals chances of winning. Let’s go through them, in chronological order.

3rd inning, Royals down 2-1, 0 outs, man on 1st, Alcides Escobar batting

Mike Moustakas had led off the inning with a single, so the Royals had the top of the order coming up, but Yost still used Escobar — the team’s worst hitter, worth noting — to move Moustakas to second base. The win expectancy of trading the out for the baserunner advancement was -2.1%, but that’s an average that doesn’t take the specific hitter and pitcher into account. Given Escobar is a lousy hitter and Lester a good pitcher, this was probably less harmful than that, and of course, you have to include the possbility that the A’s had not defended the play well and Escobar had reached safely, which would have been a strongly positive result for the Royals.

Factoring in the chance of a great Escobar bunt or the chances of an A’s misplay, this bunt was probably more of a slight negative than a big blunder. It’s not a bunt that I liked, or would support on a regular basis, but the marginal effect was probably less than 1%. Overall, I’d call it a bad bunt, but not a disater.

9th inning, Royals down 7-6, 0 outs, man on 1st, Alcides Escobar batting

Once again, a leadoff single has put the tying run at first base, and again, Yost asks Escobar to move the runner to second base. This one, though, I absolutely hated, because immediately after Josh Willingham singled, Jarrod Dyson was sent in to pinch run. Jarrod Dyson has an 86% success rate on stolen bases in his career while running on 31% of his stolen base opportunities. In other words, he’s an extremely aggressive base stealer, and he’s rarely thrown out even though teams know he’s very likely to run, especially when inserted as a pinch-runner.

Giving up Escobar’s out to move Dyson to second base felt like a complete waste, given Dyson’s speed and Norris’ problems preventing stolen bases. And the Win Expectancy of giving up the out for the first to second advancement was -4.9%, putting in almost even with Billy Butler’s baserunning blunder in the first inning. Giving up an out –lowering your Win Expectancy by 5% — to move a fast runner from first base to second base is almost the definition of bunting to lose.

Except here’s the thing: Dyson then promptly stole third, putting himself 90 feet away with only one out, meaning he could score without the Royals needing to get a base hit. That stolen base had a Win Expectancy gain of 13.3%, so the team’s WE moved from 31.5% after Willingham’s single to 39.9% after Dyson’s steal, even factoring in the out surrendered in the process. Getting Dyson to second wasn’t that valuable, but getting him to third was extremely valuable, and the bunt enabled him to steal third in the first place.

Had the order been reversed, and Dyson stolen second base before Escobar bunted, we probably wouldn’t see this as a bad bunt. Getting that runner to third with less than two outs is a big deal, especially when its the tying run in the 9th inning against a very good pitcher who is unlikely to allow a big rally. Maybe the ideal would have been to have Dyson steal second and third, but perhaps the Royals believed that their aggressiveness in the previous inning would have the A’s pitching out during Escobar’s at-bat, making Dyson’s chance of stealing second less likely. This is where game theory really comes into play, and makes the decision extremely difficult to analyze.

So, yeah, I hated the bunt to move Dyson to second base, but we can’t ignore that the bunt allowed Dyson to steal third, and the combined effects of the bunt and steal were very strongly positive for the Royals. We could debate whether or not it would have been better to have Dyson steal twice and give Escobar a chance to try and drive him in as well, but I don’t know that I can call that a bad bunt with the knowledge that Dyson would then immediately try and take third. Seen together, the bunt and steal helped the Royals tie the game.

10th inning, tied 7-7, 0 outs, man on 1st, Chrisian Colon batting

Another leadoff single, and another bunt to second base. However, because one run is all you need as the home team in a tied game in extra innings, the cost to surrendering the out and reducing your chance of a bigger rally is significantly diminished. This is exactly the situation where playing for one run makes the most sense, as there is no value in scoring additional runs beyond the first one.

Thus, the win expectancy for the out/advancement trade-off here is only -1.1%, half of what it was in the third inning, when multiple runs still had value. Dropping 1% in Win Expectancy with the out means that this is basically a neutral or even positive play once you factor in the chances of the A’s not successfully defending the bunt. At worst, this was probably a lateral move, or something close to it, and this bunt deserves no real criticism.

11th inning, tied 7-7, 0 outs, man on 1st, Jarrod Dyson batting

Another inning, another leadoff single, another bad hitter making the out/advancement trade-off. Only with Dyson, the bunt is probably an even better play than usual, as 40% of his career bunts have resulted in hits. Bad hitters with great speed have even more incentive to attempt bunts because of the higher likelihood of reaching safely if the defense doesn’t play it perfectly, and again, we’re looking at a -1.1% cost in Win Expectancy even when the A’s do convert the out at first base.

This was not only an entirely defensible bunt, but probably the right call.

So, all told, we have four sacrifice bunts by Yost last night, and they break down something like this:

Probably Negative: 1

Unknowable Gray Area: 1

Probably Positive: 2

Ned Yost bunted a lot last night, but it’s not at all clear that Ned Yost hurt the Royals chances of winning by frequently calling for sacrifice bunts with his worst hitters. The third inning bunt is criticism-worthy, I think, and the 9th inning bunt might have been too, depending on what you think of the odds of Dyson being able to steal second sucecssfully without it interfering with his ability to also steal third, but the extra inning bunts were just fine.

It’s fine to be against giving up outs. In general, good hitters shouldn’t bunt, and teams shouldn’t be playing for one run too often early in games. But in late game situations where one run is paramount, bunting can often be the correct play, and the don’t-bunt-ever reaction can be just as incorrect as the bunt-always fanaticism.