2017 MLB Relief Pitching at the ASB

This article fulfilled multiple requests for an article on the value of handicapping relief pitching in MLB.  It will compare 3 different ways to analyze a successful bullpen speaking to reasons of past or current success of each measure.  All numbers used for this article are through the All Star Break, July 13, 2017.  Before I give an explanation of the methodology, a bit of reflection is necessary as a back drop for any bullpen article of 2017.

It is now been many decades since MLB teams used an “iron 4” pitching rotation.  This starting rotation went out every 4th day of a 150 game season pitching mostly between 7 and 9 innings regardless of arm fatigue.  That meant the handicapper could make the starter a predominant part of the handicap and only factor in a late inning closer with his availability.

All of that has changed considerably in the last 60 years.  Now ownership and managers are far more conservative in their use of starters.  In the 2017 season (whether it is live balls) a smaller strike zone, better hitting, or worse pitching which is leading to an outburst of runs (it is factual) that MLB starters are now lasting on average less than 6 IP/game.  The balance of the innings are taken up by 4 categories of bullpen pitchers including long relievers, middle relievers, set up men, and closers.  Good luck deciding which of those relief pitchers will throw on any given day.  In short, specifically handicapping relief pitchers has become a crap shoot.  So what could be done to make our best effort to incorporate the work of the bullpen as a part of the handicap.

The chart below represents 3 different ways of analyzing a bullpen’s efficiency.  Those numbers include the OPS (on base % + slugging %), the ERA, and a more unique relief pitching index including strand % and save %.  A team’s record at the All Star Break will be used as a method of comparison.  One quick note; the strand % is an inverted number of runners inherited who scored for the relief pitching staff.  That number is derived by subtracting the inherited runners who scored from 100.  This strand rate is then added to the save % for the pitching index.


To draw conclusions from these ratings and rankings would be tough to do.  The data does not lend itself to the type of rank analysis that is done with the buy and sell ratings.

It can, however, be noted that the OPS and ERA numbers tend to be more representative of a team’s overall success than the Save + Strand numbers.  These latter numbers would be more valuable when analyzing the later innings of a bullpen’s work.  Regarding individual teams, the following conclusions might be reached.

Cleveland Indians – The top ranked bullpen by all 3 measurements.  Yet last year’s World Series rep continues to struggle because of poor play at home and with underachieving bats and spotty work from the bottom of their rotation.

Houston Astros – The Houston success is highly attributable to an offense that not only hits well but performs well on the base paths.  If they are going to win the whole thing, their strand % must improve.

Washington Nationals – Similar to Houston with arguably the best offensive numbers in MLB as it has been all year.  The bullpen is the weak link.  Expect a trade to shore up this efficiency in the next two weeks.

Boston Red Sox – Unlike previous seasons with Big Papi leading the way, the Boston hitting is middle of the pack showing the importance of their strong relief numbers as being a reason for their current Division lead.

Chicago Cubs – The defending champs can’t blame their bullpen for their struggles at the mid-way point.  Look to an offense which has dropped to the middle and a group of last year’s starters whose ERA & OPS numbers are significantly worse. Quintana to the rescue?

Cincinnati Reds – The Reds have top pitching numbers in all 3 categories.  Maybe they should insert some of them as starters into a rotation whose 8.97 OPS is easily the worst in MLB.

Chicago White Sox – Finally, note the Pale Hose outstanding relief numbers proving that it takes more than a bullpen to reach the upper echelon of MLB.

The above study makes it clear to this author that finding a link between bullpen success and a team’s W/L number is hard to come by.  It is a further indictment of the fact the increased role of the bullpen, without knowing exactly who will be pitching, continues to make handicapping MLB a most challenging experience.

Posted in: MLB

Leave a Reply

Your email address will not be published.