Steals are an important statistic in fantasy baseball. They represent 10% of scoring categories in 5x5 leagues and earn an equivalent value or more to singles, runs and RBI in points leagues. Comparing runs and stolen bases, the fantasy significance of a steal is certainly overvalued versus its real baseball relevance.

The Run Expectancy table (RE24) appears to frown upon stolen base attempts. RE24 quantifies changes in run-scoring probability throughout an inning based on number of outs and runners on base. Essentially, the incremental increase in run expectancy by stealing a base is less impactful than the detriment if that player is caught for an out. RE24 prioritizes outs over base position.

However, swipes are a fun stat. Bonus basepath robbery from Miguel Cabrera or Nelson Cruz just makes managers giddy. Similarly, on a .150 evening with negligible counting stats, scraping out a steal by Jose Altuve or Dee Gordon is salve and aesthetically soothing. Watching a steal is also thrilling. Rickey Henderson, Dave Roberts and lately Billy Hamilton all have inarguable reputations in baseball lore as exciting speed demons.

Stolen Base Background, Stats and Ponderings

How has the Stolen Base evolved? Looking at recent history, stolen bags have declined -22% from 3,229 in 2012 to barely 2,527 last season. The average number of steals per team have dropped by over 20 SBs per season. Barring a renaissance, the stat is getting scarcer and fantasy managers must adjust accordingly.

wSB is an advanced stat developed to illustrate whether a player has contributed or detracted runs by attempting steals. Unlike RE24, wSB is context-neutral (game situation is irrelevant). wSB matters because more successful steals result in higher wSB and conceivably, more green lights. wSB also penalizes getting caught so it’s another helpful measure for points leagues. As the SB gets rarer, efficiency becomes the key where fantasy managers can capitalize on the category.

To stay simple and applicable, let’s use the Billy Hamilton Era (2014-2017) as a historical observation period. The tables below display top-down steals data and individual leaders by season.

Table 1 – Aggregate steals data (Source: ESPN)

Table 2 – Individual steals leaders (Source: ESPN, Fangraphs)

Table 1 shows the extremes of team steals but also notes that average steals have stabilized over the past few seasons. Baltimore has been dead last for four consecutive seasons. It’s probably manager’s discretion, but why Baltimore prefers glacial baserunning is a question best left for O’s fans. Intuitively, success rate matters. The better teams steal, the more they run. The league average has hovered around 70% with the worst teams near 60% and the best teams at approximately 80%. There is a negligible difference between NL and AL totals.

Team data is useful but individual stats are handier, especially in fantasy. Table 2 is dominated by two players, Billy Hamilton and Dee Gordon. Since it is a cumulative stat, SB leaders are normally atop the wSB leaderboard too. wSB gives the nod to efficiency over volume and Hamilton’s superior success rate supports his high wSB rank.

For fantasy purposes, SB/PA is a helpful measure. SB/PA observes steals efficiency in the form of opportunities. Even though Hamilton is a .248 career hitter, he’s running whenever he gets on base. Of course, SB/PA ignores situational circumstances and the fact that PAs resulting in XBHs lower stealing chances. It’s best to look at SB/PA for soft-contact hitters. Hamilton and Gordon were last in Hard% last season and top-6 in Soft%. Success rate argues that ineffective players will get limited opportunities as managers put up the brake signal. In points leagues, success rate represents risk reward and could be a less scientific and worthy proxy to wSB.

Steals concentration is important considering the tapering of aggregate steals to this lower steady-state. Since 2014, the Top-10 players in steals have accounted for over 15% of all stolen bags in a given season! Basically, locking down a Top-10 guy puts you in very strong position for SBs. However, that may be more challenging than thought. Aside from Hamilton, Gordon and Altuve, the year-on-year steals leaderboard is a rotating door. Injuries (A.J. Pollock), slumps (Byron Buxton) or playing time (Rajai Davis) could all erode players’ value from draft day through the season. Luck, changes in team approach or countless situational variables could also steamroll perceived candidates (Jonathan Villar, Hernan Perez). Likewise, players like Whit Merrifield and Cameron Maybin often emerge from the waiver wire rubble to provide fantasy relevance. Considering the emphasis on drafting consistent and balanced players, chasing SBs exposes managers to a set of external risk factors they must weigh. A miscalculation on stolen bases could lead to a black hole in other offensive categories and frantic decision-making in the trade market or waiver wire.

Draft Strategy

Undeniably, Hamilton and Gordon are gods of the stolen base so criticism should be limited for drafting SB deities. However, due to externalities discussed, there are too many risks that argue against prioritizing steals. Pulled hammies, part-time roles, ample waiver-wire substitutes, proliferation of advanced stats and RE24 gurus are just a few examples. Focusing on steals could mean sacrificing other valuable categories like average, HR and RBI so be aware of the tradeoffs on draft day.

Alternatively, it’s better to benefit from steals as a by-product of broader hitting ability. This is why Altuve, Mike Trout, Paul Goldschmidt, Charlie Blackmon and Mookie Betts all project as first round selections. If you can’t get a five-cat stud, not all is lost. Emerging players like Francisco Lindor, Jose Ramirez, Andrew Benintendi, Wil Myers and Alex Bregman could be candidates for over-20 swipes to complement other very strong categories. Speedy vets Elvis Andrus and Lorenzo Cain are reliable and should remain serviceable. Even Anthony Rizzo and Travis Shaw got in on the action with 10 apiece. Specialists like Jose Peraza and Delino Deshields could be drafted but the wire should provide plenty of options for recruiting replacement level players. Although guys like Hamilton and Gordon are outliers, there is a high distribution of outcomes in the 10-20 SB range.

Below is a brief discussion on steals specific to formats, from most to least important.

Weekly rotisserie, head-to-head leagues – the argument against steals rests primarily on unpredictability and churn over a longer term. This doesn’t mesh with weekly leagues. Managers should ensure they have a handful of players that can nab a base or two on a weekly basis if they want to win the category.

Season-long rotisserie leagues – steals are still a 5x5 category so although they should be de-emphasized on draft day, swift decision-making and trendspotting will be greatly significant to remaining competitive. Managers will and should have to chase steals at some point during the season to pick up valuable roto points.

Points – steals matter the least here especially considering the CS penalty. The skewed nature of points for SBs compared to runs, RBI and hits should be evaluated but apples to apples, HRs outpaced SBs by 2.4x in 2017 and they’re worth more. Points leagues are category-impartial and SBs should be treated solely in the context of a player’s overall profile.

As always, manager strategy should be dynamic and shaped to league tendencies. If you love the steal, go for it. But that doesn’t mean you should reach for Eduardo Nunez in the 5th. Be patient, let the game come to you and when it does, run Forrest, run.

More 2018 MLB Advice and Analysis