Who Is The Red Sox's Best RBI Man?

The Red Sox's best RBI man is the player with the most runs batted in - but that is a coincidence.

Because RBI are a context-driven stat and a batter cannot control how many of his teammates are on base when he comes to the plate, however many runs a batter drives in is largely out of his control. In a radio interview in 2009, then-Boston GM Theo Epstein said:

Sometimes you guys [in the media] get stuck evaluating players through home runs and RBIs. It's not the way most clubs do it these days. ... [Y]ou guys can talk about RBI if you want. We ignore them in the front office. ... If you want to talk about RBI at all, talk about them as a percentage of opportunity, but it simply is not a way that we use to evaluate offensive players.

You might think that since the Red Sox front office has "ignored" RBIs for at least a decade, the men and women who cover the team might not lean too heavily on the stat, and enlighten the fans why RBIs are fairly useless and perhaps suggest a better way of measuring production. (You would be wrong.)

As Epstein said, if anyone is going to bother with RBI, look them "as a percentage of opportunity". Which makes perfect sense. Even the most statistically-adverse fan can understand that a guy who drove in 100 of 400 (25%) men on base is not a better "run producer" than the guy who drove in 70 of 150 (47%), even though the first player has 30 more RBI.

So who are the best at driving in runs on the Red Sox, through the first 45 games of the season?

First , the counting stats:

             PA  RBI
Betts       192   30
Benintendi  195   25
Moreland    183   24
Pedroia     185   21
Ramirez     152   20
Bogaerts    177   15
Leon         94   14
Young       109   12
Bradley     112   11
Sandoval     67   10

I couldn't resist putting in plate appearances, too. They tell us that some guys, most notably Sandy Leon, have clearly made the most of their opportunities. Although Leon has 83 fewer plate appearances than Xander Bogaerts, he has driven in almost as many runs.

Baseball Prospectus has, among its stats, "RBI Opportunities". The table below lists, plate appearances, number of plate appearances with runners on base, the number of men on each base when the player batted, how many runners were batted in from each base, total baserunners, others batted in (RBI-HR), the percentage of runners on each base driven in, and the percentage of all baserunners batted in.

We see that Mookie Betts, in addition to leading the team with 30 RBI, has also driven in the highest percentage of baserunners. Andrew Benintendi has batted with 22 more baserunners than Betts, but has five fewer RBI. And when it comes to converting men on second or third into runs, Leon is pretty much the best hitter on the team.

            PA PA_ROB R1   R2   R3 R1_BI R2_BI R3_BI ROB  OBI  R1BI%   R2BI%   R3BI%    OBI%
Betts      192   81   60   39   16   7    10     6   115   23  11.7%   25.6%   37.5%   20.0%
Leon        94   40   29   17    8   1     5     4    54   10   3.4%   29.4%   50.0%   18.5%
Pedroia    185   76   48   42   15   3     9     7   105   19   6.3%   21.4%   46.7%   18.1%
Moreland   183   84   59   34   23   3     7     9   116   19   5.1%   20.6%   39.1%   16.4%
Rutledge    45   21   17    8    8   0     1     4    33    5   0.0%   12.5%   50.0%   15.1%
Benintendi 195   99   70   41   26   3     8     9   137   20   4.3%   19.5%   34.6%   14.6%
Bogaerts   177   76   51   33   20   3     4     9   104   15   5.9%   12.1%   45.0%   14.4%
Marrero     45   24   17    6    7   0     2     2    30    4   0.0%   33.3%   28.6%   13.3%
Sandoval    67   38   25   18   12   2     2     3    55    7   8.0%   11.1%   25.0%   12.7%
Young      109   53   42   23   14   0     3     7    79   10   0.0%   13.0%   50.0%   12.7%
Ramirez    152   76   50   40   22   3     5     6   112   14   6.0%   12.5%   27.3%   12.5%
Vazquez     78   37   33   12    7   3     1     2    52    6   9.1%    8.3%   28.6%   11.5%
Bradley    112   55   42   20   11   1     3     3    73    7   2.4%   15.0%   27.3%    9.6%
Hernandez   60   21   15   10    3   0     1     1    28    2   0.0%   10.0%   33.3%    7.1%
Holt        19   11    6    6    4   0     0     1    16    1   0.0%    0.0%   25.0%    6.2%
Selsky       9    5    2    3    1   0     0     0     6    0   0.0%    0.0%    0.0%    0.0%
Travis       4    2    2    1    0   0     0     0     3    0   0.0%    0.0%    0.0%    0.0%
D'arnaud     1    0    0    0    0   0     0     0     0    0   0.0%    0.0%    0.0%    0.0%

Who are the MLB leaders in OBI%? Looking at players with at least 90 plate appearances, here's the Top 10:

Charlie Blackmon (Rockies)  29.2% (Leads MLB with 42 RBI)
Nomar Mazara (Rangers)      24.8%
Adam Eaton (Nationals)      24.4% (9th on team in RBI (on DL))
Mark Reynolds (Rockies)     23.3%
Eduardo Escobar (Twins)     23.1% (7th on team in RBI)
Travis Shaw (Brewers)       23.0%
Aaron Altherr (Phillies)    22.7%
Manny Pina (Brewers)        22.2% (11th on team in RBI)
Avisail Garcia (White Sox)  22.0%
Jean Segura (Mariners)      22.0%

Two other players:

Top MFY: Roland Torreyes, 21.3%
Mike Trout (Angels), 17.5%