One of the most exciting, positive “unknowns” about the 2011 Boston Red Sox is the combined impact Carl Crawford and Jacoby Ellsbury will have on the basepaths. 

Speculation has focused on the Sox’ newly improved hitting lineup and its strong pitching rotation, but, relatively little attention has been given to just how extraordinary it is for a team to have two of the game’s most prolific base stealers on the same side for nine innings.  

The Red Sox have never had a duo who can run this fast, and it’s rare for any team to have two of the game’s best baserunners.  Crawford and Ellsbury will have an obvious potential to increase the team’s run-scoring capacity, but perhaps their influence may go beyond that. 

It’s hard to measure the full impact of a base-stealing threat on opposing pitchers and the outcome of a game.  Yet, for one example, Red Sox fans grew painfully familiar with the undeniable impact Crawford’s speed had on many Sox-Rays games in recent years.  When he got on base, he distracted many Sox pitchers, contributed to many Rays’ rallies and was a “game-changer.”  (Remember when Crawford stole a record-tying six bases in one game last season!)

Sox fans have seen the benefit of Ellsbury routinely getting to second-base via a steal and scoring important runs.  Now pitchers will have to worry about both Crawford and Ellsbury on base at the same time.   

Sometimes people overrate base stealing.  I’ve heard Tony Massarotti on his Boston radio show with Michael Felger, “98.5The Sports Hub” frequently comment that fans tend to exaggerate the significance of base-stealing.  Massarotti has commented that Ellsbury draws disproportionate attention for his steals, but he’s flawed in other areas such as on-base percentage. 

I agree with Massarotti to a large extent, but I think he overlooks one point:  Explosive baserunners like Ellsbury and Crawford can not only distract opposing pitchers but often throw them out of their rhythm and into a bad spurt on the mound.  

That factor can lead to a team scoring a run or two and result in a win.  There is sometimes an intangible, psychological effect that goes with having runners like Crawford or Ellsbury taking a huge lead off first base.  

Ellsbury and Crawford have both put up incredible stats for steals so far in their careers. In 2008, Ellsbury’s first season in the majors, he stole 50 bases.  In 2009, he stole 70 bases—tops in the American League.  He missed most of 2010 due to his rib injuries.  Crawford, the stolen-base champ for four seasons, has stolen 40 or more bases in seven of his eight seasons, and in five of those, he had more than 50 SB.  (Injuries limited his SB total to 25 in 2008.)  He stole 60 in 2009 and 47 last year.  

The last pair of terrific base stealers on the same team were Marquis Grissom and Delino DeShields of the Montreal Expos in 1991 and 1992, according to an article last month by ESPN Boston’s Gordon Edes.  Grissom stole 76 in ’91 and 78 in ’92 while DeShields stole 56 in ’91 and 46 in ’92.  

Only once in the history of both the American League and National League have two teammates stolen 60 or more bases.   Crawford and Ellsbury may not equal that incredible combined total, but they might come close.   Their speed and presence on base could be a difference maker in whether the Red Sox go all the way in 2011.

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