Prepare yourself for a bold statement: Billy Hamilton of the Cincinnati Reds is the best base runner in the league. And it’s not even close.
I know, right? Where am I coming up with this? Well, unless you caught on to my dry sarcasm, let me explain.
Since 2015, he’s the top batter in Fangraphs all-encompassing BsR stat, tops in weighted stolen bases (or wSB), and ranks fourth in ultimate base running (UBR).
The following graphic displays, by position, the fastest base runners with a minimum of 50 opportunities (note: all data is from the 2017 season).
Those two pink dots at the far right of the image? The first one is Byron Buxton of the Minnesota Twins. The dot right next to him is Hamilton. They represent 30.2 and 30.1 ft/sec respectively; fractions of a second.
So yes, Hamilton is fast. And a terror on the base paths.
Yet the one thing working against him is his career .298 OPB; he just doesn’t get on base enough. But, that’s another conversation for a different post.
Now that we’ve sussed out my inital declaration, I want to determine which player is the best base runner who isn’t named Billy Hamilton.
The stat we are going to lean heaviest on is the aforementioned BsR. The simple formula for figuring out BsR is as follows:
Using those more specific stats, we create a complete rating for base runners.
BsR is basically the equivalent to WAR (wins above replacement) in terms of productivity on the base paths (and is actually factored in when calculating WAR). BsR is measured as runs above average that a player produces with his ability when on base. Zero is considered league average, anything eight or above in a given season is tremendous, and a negative six or below is someone who makes a lot of running mistakes.
Obviously being caught stealing, or being thrown out trying to extend a hit, is costly to a team. To provide any sort of benefit, when you steal, you better succeed at least two out of every three tries.
Now keep in mind that BsR is a historical stat and can’t necessarily be used to project future performance. Whats more, you’ll need at least a year of data before you could even start to assess future BsR. Right now, we are only interested in what has already happened.
Sprint speed will also play a role in our evaluation. See below for the fastest runners in terms of feet per second for the 2017 season; a supplement to the graphic from earlier in this post.
You can see Hamilton and Buxton head and shoulders over the rest of the group.
Speed alone doesn’t necessarily translate into a great base runner, so lets take this one step further.
Included in the following table is OBP (need to be on base), SB/CS (success rate on steals), wRC+ (how their movement can help create runs), and ISO (how often are extra base hits produced); all data presented is an average of the last three seasons.
I included Hamilton just for context since he’s not only the fastest runner but also has by far the highest BsR the league.
A quick overview of the chart could declare Mike Trout to be Hamilton’s understudy, as he tops most of the categories. He’s a fast runner and gets on base at a high rate.
However, his success ratio on stolen bases is one of the lowest on the list. Getting caught stealing, depending on the base out state of the inning, can be incredibly costly to your team.
Yet the most detrimental to Trout is his ranking of eight overall in BsR, the premise of this evaluation.
So, who is the best base runner not named Billy Hamilton?
The honor goes to Mookie Betts of the Red Sox. He’s a fast runner, gets on base a lot, has some extra base pop, and creates a lot of runs for Boston. All that plus he holds the highest stolen base success rate of all other players.
If you can’t have Hamilton on the bases for you, Betts is the next best option. And a great one at that.