Baserunning continues to be an overlooked part of baseball that is often viewed as an ancillary aspect of the game. There tends to be an oversimplification in the narrative around good baserunning that speed and talent on the bases are one and the same. Although foot speed is certainly beneficial, it is not the best way to truly evaluate play on the bases.

That is why at Sports Info Solutions, we evaluate baserunning on a plus/minus scale, with Good Baserunning Plays (GBP) resulting in a plus and Bad Baserunning Plays (BBP) resulting in a minus. GBP and BBP are based on review by our Video Scouts, who use specific criteria in determining good and bad baserunning. There are eight types of good plays and 16 types of bad plays.

The most common GBP is “Baserunner takes an extra base” which is essentially just being aggressive in taking one more base in a situation where most wouldn’t. There are other, more nuanced GBPs such as “avoiding the tag” or “quick reaction to pitch in dirt/dropped pitch.”

Here are the leaders in Good Baserunning Plays since the start of 2018:

Player Good Baserunning Plays
Javier Baez 15
Ozzie Albies 10
Billy Hamilton 9

What is remarkable about Javier Baez’s total is that six of his GBPs have come in 2019 alone, as many as or more than the 2018 total of all but 19 baserunners (and with one more GBP, that number will shrink to six).

Of those six GBPs, five have been from plays where Baez took an extra base. The sixth GBP was credited for avoiding a tag, which he managed to do five times in 2018 helping to reinforce his moniker as “El Mago.”

Another way to provide value on the bases is to simply not make mistakes, or Bad Baserunning Plays. As you can see in the table above, Albies has more GBP since the start of 2018 than anyone except Baez, but the BBP leaderboard may give some insight as to why he is not heralded as one of the most disruptive baserunners.

The most Bad Baserunning Plays since the start of 2018:

Player Bad Baserunning Plays
Francisco Lindor 13
Ozzie Albies 12
Bryce Harper 12
Ketel Marte 12
Willson Contreras 12

Most of Albies’ BBP have been on plays in which he attempted to stretch a base hit an extra base or was caught trying to advance on a ground ball (which fall into two of the BBP categories). Between his GBP and BBP, Albies was one of the most aggressive players on the bases and, with slightly better decision-making, could rise the ranks and be a real nuisance on the base paths.

Due to some players, like Albies, driving up their GBPs (or BBPs) with volume, it is best to look at Good and Bad Baserunning Plays through the context of Net Good Baserunning Plays. Looking at this leaderboard, you really start to see some of the names you would expect to see on this list based on the eye test.

Player Good BR Plays Bad BR Plays Net
Javier Baez 15 8 7
Byron Buxton 6 1 5
Jason Heyward 6 1 5
Billy Hamilton 9 5 4
Kolten Wong 6 2 4

Despite being tied for 24th for BBP since the start of 2018, Baez remains the most dangerous player on the bases, due to having more than double the number of GBPs as all but three players over that same time frame.

This year, Baez has 6 GBP already, more than double the next-closest baserunner, but also is tied for the most BBP. Still, after taking the difference, Baez is in sole possession of first place atop the Net Good Baserunning Plays in the majors.

After finishing second in this metric behind Mookie Betts in 2017, Baez’s start has him in a good position to pace the league for a second straight year.