Stuff You Cannot Lay Your Hands On: Rof, Total Zone Outfield Arm Above Average

 By John Turney 

Part of Baseball Reference's "Rtot" number (which is defined on the site as "Total Zone Total Fielding Runs Above Avg: The number of runs above or below average the player was worth based on the number of plays made. This number combines the Rtz, Rdp, Rof, Rcatch numbers into a total defensive contribution." Provided by BaseballProjection.com) is the "Rof" number.

Rof is "The number of runs above or below average the player was worth based on baserunner kills and baserunner advances."

It purports to give an estimation of effective arms in MLB. How good is it? I don't know. Mike Walsh, an excellent researcher by all accounts, also has a similar number, which is usually a lower total. Beats me, but at least we can find Rof on Baseball Reference.

The problem is Rtot and Rof, and others is they are not part of the search engine options, so we cannot easily find who the career leaders. Some pages show the yearly leaders, and that is what we used to ge the following list. 

One note, this was done my a lot of cutting and pasting and the credit goes to Baseball Projection and Baseball Reference, but there may be an error or two, but things were double-checked. Also note that there are active players listed and their totals are changing.

So here it is:

There is nothing earth-shattering; Roberto Clemente is on top, as would be expected but it's nice to see some modern players on it as well. The metric goes back to 1953, so players before that are out of luck. 

Note that this is not just outfield assists, it is holding runners and also throwing them out or "kills" so while you can find a list of assists on Baseball Reference, you have to hand sort them to analyze only outfielders. 

Take a look, see what you can make out of it, and hopefully, someday Baseball Reference will add this and other metrics to their search engine "Stathead" and then it can be messed around with by minds greater than ours and applied in new ways.