Did new rules cause big spike in MiLB steals?

Looking for action on the basepaths? Head to a High-A or Low-A ballpark.

Back in March, Major League Baseball announced that it was instituting rule changes to the four full-season levels of the Minor Leagues. At High-A, all pitchers are now required to step off the rubber fully before attempting a pickoff move. Meanwhile, Low-A hurlers are allowed only two pickoff attempts per plate appearance. These were done specifically to increase the potential for stolen bases, leading to more exciting movement around the diamond. They were also isolated to their respective levels to better study whether the specific changes were having their intended effects.

Through two weeks, the early returns point to the affirmative. Stolen bases and stolen-base attempts are up significantly at the Minors' lowest full-season levels.

"I think a lot of credit has to go to the players first because a big part of stealing bases is being comfortable and maximizing your lead," said High-A Hillsboro manager Vince Harrison, whose Hops lead the Minors with 32 stolen bases through 12 games. "That's something that's always been taught. But now, we have the rules on what type of pickoffs we can look for. ... We have some guys that can actually run and probably can steal some bases already. Add in that with playing a little more fearless, and all of that is definitely a factor [in the increase]."

Let's start at High-A and compare the first two weeks of the season with the stolen-base and caught-stealing rates of the past three Minor League campaigns, 2017-19.

The data is clear. High-A teams are attempting 50 percent more stolen bases than their 2019 counterparts with attempts up from 1.19 per game two years ago to 1.79 through the early going. It's easy to see why. With pitchers needing to step fully off the rubber, runners are extending their leads and getting better jumps than ever, once they know the man on the mound is actually delivering the ball home.

Those leads and jumps have led to a sharp dropoff in caught-stealing rates as well. Pretty steadily, catchers were throwing out between 32.6 and 32.8 percent of opposing baserunners over the previous three seasons. That has dropped to 20.9 through the first two weeks of 2021.

"Prior to this year, you're looking for what [a pitcher] is doing with his feet or, with a lefty, you have to consider the read move," Harrison said. "This year, that's not in play with the lefties. With the righties, you're looking for a complete step back. It takes away two things you have to worry about. Guys are just getting more comfortable trying to take more in that initial lead, knowing that there are certain things they don't have to look for."

Hillsboro, affiliate of the D-backs, already boasts 12 players with at least one stolen base in these first two weeks and successfully stole 11 bases in one game on May 7 against Everett. In all, five of the seven clubs with the most steals in the Minor Leagues are from the High-A level.

Of course, some of this could be noise in an early small sample, and defensive rustiness on the part of catchers caused by the lack of a 2020 season could be in play as well. But this steep of a change matched by a specific rule alteration is notable early on.

The story is much the same at the Low-A level.

Fans at a Low-A game in Florida, California or along the Mid-Atlantic are slightly less likely to see a stolen-base attempt than their High-A counterparts, but they are more likely to see a successful theft.

Stolen bases per team per game are up 71.1 percent at Low-A compared to 2019 while the caught-stealing rate has been nearly cut in half. Again, rustiness may play a part in the latter (especially for young catchers who may lack the in-game experience of Low-A backstops of previous years), but what can't be overlooked is the new pickoff rule specific to this level. Since pitchers aren't allowed to throw over a third time or else risk a balk on an unsuccessful pickoff, Low-A runners can get an extraordinary jump the moment the hurler moves.

"We did it a couple times already," said Low-A Fresno manager Robinson Cancel, whose club ranks second in the Minors with 31 steals in 12 games on the young season. "Guys have thrown over or sometimes pitchers will step off because maybe they don't want that pitch and they want another sign. But we count it, and we take advantage. We take a bigger lead and probably force them to throw over again with little stuff like false breaks and other things. Hopefully they step off one more time, and then we can take advantage again."

To show just how isolated this is to the two lowest full-season levels, dive into the stolen-base numbers from Double-A and Triple-A:

The stolen base rates at Double-A are comparatively stagnant to this point. The second-highest Minor League level's biggest rule change involves keeping the infielders on the dirt (i.e. limiting the shift), and that hasn't affected steals, nor was it intended to do so. For all intents and purposes here, Double-A is serving as the stolen base control early in 2021.

There have been some gains at Triple-A, though they are a far cry from what's happening much lower. The Minors' top rung is using larger, 18 square inch bases this season (up from 15 inches in the past) and grippier material on the bags meant to limit injuries resulting from slickness. Bigger bases mean less distance from station to station but not quite enough to lead to the large jumps we're seeing elsewhere.

Like so much about the return of Minor League Baseball in 2021, these early stolen-base trends are worth following as sample sizes grow larger and pitchers and catchers alike adjust to the new rules. For now, the data is clear. High-A and Low-A are the places to run wild.

"I think in the long run it's going make a lot of people better because pitchers are gonna get better at figuring out their times, messing up runners' leads and stuff like that," Harrison said. "Overall, it's gonna be a good thing for everybody, not just the baserunners."

"As long as we're on base, we're going to be aggressive on the bases," Cancel said. "We're gonna keep going."

These are some notable prospects taking advantage of the new rules thus far:

Marlins SS Nasim Nunez, Low-A Jupiter (No. 13)
Nunez swiped 28 bags in 51 games in 2019 between two short-season clubs, so he’s no stranger to the theft. This is still something new for the 65-grade runner. His 11 steals in 10 games so far are the most in the Minors, and there might be bunches more where that came from. Nunez swiped four bags in one contest alone on May 9 against St. Lucie.

Rockies OF Zac Veen, Low-A Fresno (No. 1, MLB No. 43)
The Rockies snagged Veen with the ninth overall pick because of his abundance of tools. That said, the left-handed slugger has only one skill that grades out below a 55, and that is his 50-grade speed. That hasn’t stopped him from stealing 10 bases through 11 games with Fresno, making him the leader in Low-A West. Veen makes up for his speed by getting huge jumps off pitchers limited by the new pickoff rule, as he did this weekend on this straight steal of home.

Yankees SS Oswald Peraza, High-A Hudson Valley (No. 4)
Peraza, a plus runner in his own right, once led the Minors himself with nine stolen bases through his first nine games with the Renegades but hasn’t swiped a bag in his last three contests. What changed? He started hitting homers. Peraza went deep five times last week alone. Can’t steal a base if you’re trotting around them. His nine thefts remain first in High-A East, three more than his closest competition.

Rockies 2B/SS Eddy Diaz, High-A Spokane (No. 21)
Diaz stole 104 bases over his first three seasons in the Colorado system, so it was always a safe guess that he would enjoy the extra green lights that could come in 2021. True to form, the 65-grade runner has swiped seven bases in 10 games with Spokane, placing him third among High-A West baserunners.

D-backs SS Blaze Alexander, High-A Hillsboro (No. 17)
Had to get a Hillsboro player in here somewhere. That could have been top Arizona prospect Corbin Carroll and his three steals, but his season-ending shoulder surgery will rule him out from adding to that total the rest of the way. Alexander, meanwhile, has what evaluators believe to be average speed, but he has still managed four stolen bases in his first 11 games with the aggressive Hops. His career high is 14, set in 2019 with Class A Kane County, and he is well on his way to blowing past that as early as next month.