What Happened to All Those Stolen Bases?

Texas Rangers center fielder Leody Taveras steals second base against Houston Astros second baseman Jose Altuve in the third inning during Game 2 of the ALCS at Minute Maid Park.
Troy Taormina-USA TODAY Sports

The 2023 regular season looked a bit different from previous years. MLB made some significant rule changes back in the spring — adding a pitch clock, limiting defensive shifts and pickoff attempts, and larger bases among them — and those changes, for the most part, had their intended effects. The pitch clock helped shorten the average nine-inning game by nearly half an hour; scoring increased by more than a half a run per game; and with pitchers now under the gun to deliver to the plate and limited in their ability to check on the running game, and with a slightly larger target 90 feet away, baserunners became historically aggressive. Stolen bases jumped from 0.51 per team per game in 2022 to 0.72 in ’23, a more than 40% increase and the highest average per team game since 1997, when there were also about twice as many baserunners caught stealing as there were in 2023. Never in the more than 100 years of available data have teams averaged as many as 0.72 steals per game and as few as 2023’s 0.18 caught per game.

But so far in October, stolen bases have been a relative non-factor, with teams averaging just 0.50 per game in the postseason, lower than last year’s regular-season rate. It’s still higher than last postseason’s rate of 0.43, but well within the pre-rule change range of norms.

Stolen Bases Per Team Game
Season Reg Post
2023 .72 .50
2022 .51 .43
2021 .46 .59
2020 .49 .35
2019 .47 .46
2018 .51 .53
2017 .52 .28
2016 .52 .59
2015 .52 .64
2014 .57 .47

Let’s start with the obvious: runners are getting caught only slightly more frequently than they were in the regular season. They posted the two highest league-wide stolen base success rates of all time at 75.7% in 2021 and 75.4% in 2022, only for that figure to jump to 80.2% in the 2023 regular season. So far in October, they’re at 78.4%.

But this difference of less than two percentage points doesn’t explain a 40% drop in overall stolen base numbers. Indeed, if we look at overall attempts, the per-team-game average went from 0.68 in 2022 to a remarkable 0.90 in ’23 — and then back to 0.64 so far in these playoffs. For the most part, it’s not for lack of success; it’s for lack of trying.

SB Attempts Per Team Game
Season Attempts/TG Reg Attempts/TG Post
2023 .90 .64
2022 .68 .55
2021 .60 .65
2020 .66 .46
2019 .64 .53
2018 .71 .77
2017 .71 .39
2016 .73 .73
2015 .73 .81
2014 .78 .63

And it’s not just that teams aren’t running as much; stolen bases just don’t seem to be having much of an impact altogether. The 29 stolen bases through Thursday’s games had summed to a total of .396 WPA; compare that to the 2022 postseason, when 34 stolen bases amounted to a WPA of .679. Last October, 12 successful stolen base plays swung a team’s odds of winning a game by at least two percent. This postseason, just four have, including two in the ninth inning of Thursday night’s walk-off Diamondbacks win. In other words, baserunners are not only picking fewer opportunities to go, but also picking lower-leverage ones. In last year’s postseason, the average plate appearance leverage index when a runner took off was 1.29; this year, it’s 1.16.

When runners have picked a high-leverage spot to go, it hasn’t gone so well. Most notably, Gunnar Henderson’s ninth-inning caught-stealing in ALDS Game 1 — which, to be fair to him, was later revealed to have been a busted hit-and-run — cost the Orioles to the tune of -.221 WPA, still the sixth-most pivotal play in these playoffs. No other caught-stealing comes close to that one, but other higher-leverage attempts have gone awry as well. Of the top 15 attempts this postseason by leverage index, nine have made it safely, and six have been caught.

What could be the culprit for the lower rates? In the postseason, we’re looking at a much smaller sample than in the regular season, and the rate at which teams are attempting to steal bases could be impacted by the rate at which teams are getting on base, the players who are getting on, the ability of the specific pitchers and catchers to protect against stolen bases, and more. The sample size means that these averages can be swung by, for instance, the fact that Ronald Acuña Jr., the league’s top base stealer by nearly 20, played only four games and reached base only five times (he went 2-for-2 in stolen base attempts). Corbin Carroll, the no. 2 base-stealer in 2023 by sheer volume, has been on base a ton but has been uncharacteristically shy; the TBS broadcast team could hardly believe he was staying put when he reached on an error to lead off NLCS Game 2 on Tuesday night. Had Acuña gotten a chance to play deeper into the playoffs, or had Carroll been quicker to pull the trigger to this point, we could be telling a different story.

But this doesn’t seem to be a matter of opportunity. While batting averages and on-base percentages have been down slightly in the postseason, offenses have had just about as many plate appearances in the more favorable base-stealing situations. They just aren’t biting.

Percentage of PA by Base State
Base State Regular Postseason
1– 18.3% 19.6%
12- 6.8% 6.6%
1-3 2.9% 2.6%
-2- 8.5% 6.7%
Total 36.5% 35.5%
SOURCE: Statcast

It’s not only that the sample is small in the postseason, though; it’s also not necessarily representative of the league as a whole. Just 12 of the 30 teams make it to October, and if those 12 include an overrepresentation of particularly steal-friendly or steal-averse teams, it would make sense to see those patterns in the postseason.

As it turns out, this crop of postseason teams is pretty representative of the league from a baserunning perspective. The Rays, Diamondbacks, and Phillies were among the most aggressive teams in baseball this season stealing bases, with the latter two also among the best from a success rate standpoint. The Rangers, Twins, and Marlins, on the other hand, were well below league average in the running game. Together, these 12 teams averaged 0.89 attempts per team game, compared to the league-wide average of 0.90, with a success rate of 81.2%, one percentage point above the league. When adjusted for how many games they’ve played in the postseason, you’d expect a tournament-wide rate of 0.88 attempts per game based on their regular-season performance — a far cry from what we’re seeing.

Playoff Teams’ Regular Season SB Stats
Team SB CS SB% Att/G
TBR 160 41 79.6% 1.24
ARI 166 26 86.5% 1.19
PHI 141 26 84.4% 1.03
ATL 132 27 83.0% .98
MIL 129 28 82.2% .97
HOU 107 32 77.0% .86
BAL 114 24 82.6% .85
TOR 99 34 74.4% .82
LAD 105 25 80.8% .80
MIA 86 21 80.4% .66
MIN 86 18 82.7% .64
TEX 79 19 80.6% .60

When it comes to preventing the running game, this batch of teams kept their opponents in check a little bit better than that. As a group, they allowed an average of 0.87 attempts per game, but the Diamondbacks, Rangers, Phillies, and Twins — four of the five teams with the most games played this postseason — are all bringing that average down. Weighted for their postseason games played, this group averaged 0.84 attempts per game in the regular season and kept their opponents to a 78% success rate.

Playoff Teams’ Regular Season SB Against Stats
Team SB CS SB% Against Att/G
ARI 84 33 71.8% .72
ATL 128 28 82.1% .96
BAL 88 31 73.9% .73
HOU 127 31 80.4% .98
LAD 142 29 83.0% 1.06
MIA 130 23 85.0% .94
MIL 121 23 84.0% .89
MIN 94 30 75.8% .77
PHI 104 28 78.8% .81
TBR 101 20 83.5% .75
TEX 91 31 74.6% .75
TOR 131 24 84.5% .96

The catchers on these postseason clubs deserve a lot of that credit. On Statcast’s catcher throwing leaderboard, the Diamondbacks’ Gabriel Moreno ranks as the top backstop in baseball by catcher CS above average. The Rangers’ Jonah Heim, the Braves’ Sean Murphy, the Astros’ Martín Maldonado and Yainer Diaz, and the Phillies’ J.T. Realmuto were all in the top 20 of 63 graded catchers this season. Heim, Realmuto, Maldonado, and Moreno are the four catchers with the most starts in the postseason. By team, all four Championship Series clubs were among the top 11 in the league by the same metric.

Top Postseason Catchers Defending the Steal
Player Team CS Above Average
Gabriel Moreno AZ 9.2
Christian Bethancourt TB 5.2
Jonah Heim TEX 4.8
Sean Murphy ATL 3.7
Yainer Diaz HOU 3.6
J.T. Realmuto PHI 1.8
James McCann BAL 1.7
Martín Maldonado HOU 1.6
Adley Rutschman BAL 0.5

This type of talent behind the plate tends to have a compounding effect in terms of limiting stolen bases. Not only are these catchers better equipped to throw out the would-be stealers that do run, but they’re also likely to dissuade those runners from trying in the first place. That’s not necessarily a good thing; these teams may wish they were tested more often, giving their strong catchers a chance to keep opposing runners under the success rate necessary to break even on stolen base attempts. With the stakes as high as they are, it seems that teams aren’t inclined to test them as much.

Not to worry; in all likelihood, someone will steal America a taco next week. But it does strike me as interesting that after a season of baserunners wreaking havoc on the basepaths, we’re seeing a much more conservative running game in these games that matter most. Aggressive baserunning is part of what got some of these teams to this point. As the stakes get even higher, we’ll see how judicious they are when picking their spots.

All stats through games of October 18.





Chris is a data journalist and FanGraphs contributor. Prior to his career in journalism, he worked in baseball media relations for the Chicago Cubs and Boston Red Sox.

9 Comments
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Ivan_Grushenkomember
4 months ago

I’m surprised the Diamondbacks aren’t running all the time. It’s not like their offense has a load of other ways to score

MikeSmember
4 months ago
Reply to  Ivan_Grushenko

Might be a lack of opportunities. Their team OBP in the post season is only .311. I’m not sure how often they have had people on base with an empty base in front of them.

tung_twista
4 months ago
Reply to  MikeS

Diamondback’s team OBP in the regular season was .322 (14th in MLB) and that did not stop them from being 2nd in SB.