For the fifth straight year, the Dbacks have been one of the best baserunning teams in baseball. In fact, per BBREF’s measure, the Dbacks have been the #1 team in each of the past five years except for last season when the team finished third. In each of these five seasons, the team has been at least 10 runs above average on the base paths. And since Mike Hazen took over as GM, the Diamondbacks have had an increased focused on defense as well, with their 137 fielding runs above average the best in baseball since 2017. The Diamondbacks are dominating baseball when you combine the two (or even focus on one):
Keep in mind that this is runs above average, not just total runs added. Being 171 runs better than the average team over three seasons is a huge deal! That’s an average of an extra 57 runs the Diamondbacks are adding outside of the standard value provided by hitting and pitching. To help put these extra 57 runs into context: the 2018 Reds finished with a team-wide OPS+ of 95, meaning they were 5% worse than league average as hitters. Over the course of a full season, that equated to 54 runs below average for the Reds offense.
In other words, the Diamondbacks are adding an extra 5% of value to their offense thanks to their baserunning and defense.
(Note: defense doesn’t add to your offense, obviously. This comparison is just to show the magnitude of the impact that this excellent defense and baserunning have added to the team’s overall performance)
Obviously 5% is a small difference, especially when compared to the overall value that hitting and pitching provide. But it narrows down a bit: the top offensive team in baseball this season has a 119 OPS+ (Houston Astros) and the worst offensive team has a 76 OPS+ (Miami Marlins). This is a 43% difference between the two; that extra 5% in TOTAL value is actually an increase of about 11.6% because the window of the best and worst offensive teams is much smaller than a linear scale from 0-100.
Today we’re going to look at baserunning. And while it’s a smaller component than fielding, it’s still important nonetheless.
So how are the Diamondbacks winning on the base paths?
Stolen bases are the most obvious. And it’s no surprise - the Diamondbacks like to run a lot. Over the past three seasons, the Dbacks are 10th in baseball in stolen bases with 253. In 2019, they are 9th with 71 stolen bases. Now, that doesn’t seem particularly compelling, does it? At least not to be “dominant” as this article is claiming.
The thing with stolen bases is that efficiency matters. A LOT. An out on the basepaths is much more worse than a single stolen base is helpful. The “common knowledge” is that teams need to be succeed roughly 67% for stealing bases to be worth it. However, modern analysis has shown this break-even point to be even higher. Per the study done at FanGraphs, the break-even point for stolen bases changes based on the base that you’re stealing and the number of outs:
2nd Base: The range is between 70% and 75% based on the number of outs.
3rd Base: 78% for 0 outs, 69% for 1 out, and 88% for two outs.
Home: 87% for 0 outs, 70% for 1 out, and 34% for two outs.
So the range of outcomes here is pretty dynamic. While the home base break-even points are pretty fascinating, can anyone steal home even 34% of the time? Seems highly unlikely.
2nd and 3rd, however, have some important considerations. Stealing 2nd has the lowest break-even point for success and as such, is the most common base that is stolen. 3rd base, though, has much higher requirements for success, at least with 0 and 2 outs. With 0 outs, you obviously still have the ability to move to third on a grounder, a deep fly, or a hit; why risk an out unless you’re sure you can succeed? And with two outs, why risk ending an inning when you need a hit or error to score you regardless?
Suddenly, we have some pretty high criteria for stolen base success. Having a lot of stolen bases isn’t value-added if you get caught a lot of the time as well. As teams have become more and more analytical, the number of stolen bases has dropped dramatically. And the numbers will support this.
In 2019, only 7 teams have a successful stolen base percentage (SB%) over 75%. Then there is the Arizona Diamondbacks, clocking in at a whopping 86.5%, easily the best in baseball:
This 86.5% success rate is important for two reasons - first, and most obviously, it provides tons of value compared to every other team. Second, this success rate is bordering on historic. Only two players in MLB history (minimum 80 SB attempts) have a higher career success rate than the Diamondbacks, as a TEAM, have in 2019: Alex Casilla (87.9%) and Chase Utley (87.5%). The Diamondbacks, as a team, have been better than all but two qualified baserunners in the history of baseball.
But that’s not the only historic consideration. Since 1920, only 38 teams have achieved a SB% greater than 80% over a full season (including the Dodgers, Cardinals, and Dbacks this season). The Diamondbacks have done it twice already in 2006 and in 2017. The all-time record is 87.9% by the 2007 Phillies (see: Chase Utley). Through the middle of July, the Dbacks were sitting right at 90%, which would have been a monumental feat. However, a string of caught stealing (including 3 over a 4 day period from Aug 10 - Aug 13th) have dropped the success rate down to the current 86.5%. There is still time for the Dbacks to set the record for team SB%, though with 11 current caught stealing, the team needs to get to 99 stolen stolen bases without getting caught again (99 out of 110 is 90% exactly) if they want to achieve the mystical 90% club. That’s 28 more stolen bases without being caught - probably not going to happen.
What makes the Dbacks so good at base stealing? Speed is one factor. The Diamondbacks have the single fastest player in baseball - Tim Locastro. In only 159 PA, Locastro has stolen 11 bases without being caught. The Dbacks also have Jarrod Dyson who ranks in the 84th percentile for speed, with 27 SB against only 3 CS (a convenient 90%). But beyond those two, only Nick Ahmed ranks in the top 25% for speed and he’s not a huge base stealer (though he is tied for 4th with 7 SB). The rest of the team is full of mostly average or a bit above average runners, but this isn’t a team full of blazers stealing a bunch of bases. Outside of Dyson and Locastro, it’s primarily choosing the right spots and right times to steal.
The Diamondbacks have been so successful because they pretty much only steal second base. Remember how the criteria for breaking even at stealing third jumps quite a bit over stealing second? Well, the Diamondbacks have only attempted 4 steals of third all season long. This is the fourth-lowest total in baseball. Not only are the Diamondbacks focusing on the best base to steal, they are also the most efficient team as stealing second as well.
The last factor of base stealing is not getting picked off. And again, the Dbacks excel here. Only one team has been picked off less times than the Diamondbacks.
Simply put, the Dbacks have been the most efficient base stealing team in baseball and by a hefty margin.
Extra Bases Taken
Though not quite as exciting, this is another area where the Diamondbacks are excelling at. At 44%, the Dbacks are 5th in baseball at taking extra bases: this means going from first to third on a single, scoring from first on a double, or scoring from second on a single. Here are how often the Dbacks take extra bases in each of these three situations and how they rank in baseball:
1st to 3rd on a single: 39.9% (1st in MLB)
1st to home on a double: 29.9% (28th)
2nd to home on a single: 60.5% (15th)
This pretty much summarizes the team’s philosophy: be safe and be efficient. The Diamondbacks are aggressive on taking third on singles, and this is arguably the safest of these bases to take here, especially on singles to CF and especially RF. The other two involve getting thrown out at home, which is obviously the riskiest place to get thrown out.
To hopefully no one’s surprise, the Diamondbacks have been thrown out at home the least times in baseball. And it’s not simply a lack of trying - they’ve scored the 18th-most runners in these two situations combined. They’re just being cautious and efficient when they do it.
Speaking of outs on the bases (aka “TOOTBLAN” or “thrown out on the bases like a nincompoop”), the Dbacks have the second-fewest number of outs on the bases (which does not include caught stealing). The base they have been thrown out most is 2nd, and even that is only the 15th-highest in baseball. They have the third-fewest outs at 3rd and as mentioned above, the least times at home. Runners at 3rd and home (obviously) are the most valuable runners in baseball and the Dbacks have been among the best at not throwing away outs there.
Have the Diamondbacks been too cautious? Are they keeping too many runners at third instead of sending them home? It doesn’t appear to be so. They are 9th-best in baseball at scoring runners from third with less than two outs (53.2%). They also have the 7th-best rate at scoring a baserunner on any given play (15.7%). It would be nice if there were more filters that could be used to see more specific situations, but this is all that’s available. The Dbacks have the 8th-highest ball-in-play percentage and putting a ball in play is important for scoring runners from 2nd and third. By being cautious, the team is not throwing away outs and playing to their strengths to frequently put balls into play and score runners from 2nd and 3rd.
So there you have it. A combination of uber-efficiency while still maintaining a good volume of stolen bases and extra bases taken and you have the best baserunning team in baseball for the fourth time in the past five seasons.