The Measure of a Middle Reliever

In this age of exhaustive statistical analysis, the evaluation of relief pitchers has remained an elusive skill to quantify with a simple formula. Closers, obviously, are judged by the number of saves that they amass in a season and the percentage by which they convert their save opportunities. But the rest of the bullpen cannot be judged by such standards, unless you count the “Hold”, which is a start on the quantification of quality.

ERA is a nice statistic if a relief pitcher starts and finishes an inning as all of the runs earned are of that pitcher’s making. But that rarely happens with middle relievers as they often pitch for such a short period of time that their ERA becomes skewed one way or another, depending upon how the OTHER pitchers who precede them and follow them perform.

Let’s say that Aaron Fultz relieves Paul Byrd with two men on and two outs, allows both to score via singles, then gets the final out with a fly out. He’s credited with pitching a 1/3 inning with no earned runs while Byrd is charged for Fultz’s inability to get the third out. Sure, some of the onus lies at Byrd’s feet for allowing the base runners in the first place, but if a primary function of a reliever is to get his team out of jams, ERA has its limitations.

An enormous portion of being an effective relief pitcher is an ability to strand inherited runners. That is, if Rafael Betancourt comes on with the bases loaded and two outs and is able to get out of the inning without giving up a run, he has been far more effective than Fultz in the previous example while both will simply be credited with zero ER in 1/3 IP.

Well, it turns out that such a statistic does exist (though not as easily obtained as you might think it would be) and the statistic is simply Inherited Runners Stranded Percentage, or IRS %. Essentially, you can calculate the number of Inherited Runners that a pitcher strands on the bases against the number that he allows to score to determine the effectiveness of that pitcher when coming into a game with runners on base.

It’s easy to look at a relief pitcher’s WHIP and ERA and say that they are doing well or struggling, but it really requires the IRS % into the equation to truly determine how effective relievers have been for a team.

So, without further ado, using only pitchers who have inherited 10 or more runners this year, the highest IRS %, as of Monday June 4th, break down like this:

Player – TEAM – ERA, IRS% (Inherited Runners/Inherited Runners Stranded)
Rafael Betancourt – CLE – 1.54 ERA, 100% IRS (15/15)
Aaron Heilman – NYM – 3.42 ERA, 100% IRS (14/14)
Justin Speier – LAA – 1.69 ERA, 100% IRS (13/13)
Michael Wuertz – CHC – 3.38 ERA, 100% IRS (13/13)
Sean White – SEA – 7.03 ERA, 100% IRS (10/10)
Pat Neshek – MIN – 1.33 ERA, 94% IRS (17/16)
Chin-hui Tsao – LAD – 3.00 ERA, 93% IRS (14/13)
John Grabow – PIT – 5.28 ERA, 93% IRS (14/13)
Tony Pena – ARI – 2.79 ERA, 92% IRS (13/12)
Trever Miller – HOU – 6.75 ERA, 92% IRS (12/11)
Hideki Okajima – BOS – 1.27 ERA, 92% IRS (12/11)
J.J. Putz – HOU – 1.48 ERA, 91% IRS (11/10)
Chad Qualls – HOU – 4.55 ERA, 91% IRS (11/10)
Joe Beimel – LAD – 3.65 ERA, 90% IRS (20/18)
Brian Moehler – HOU – 7.27 ERA, 90% IRS (10/9)
Scott Downs – TOR – 3.80 ERA, 90% IRS (10/9)
Jeremy Accardo – TOR – 1.07 ERA, 90% IRS (10/9)
Taylor Tankersley – FLA – 6.48 ERA, 88% IRS (16/14)
Jay Marshall – OAK – 5.40 ERA, 88% IRS (16/14)
Bobby Seay – DET – 5.28 ERA, 86% IRS (14/12)
Jason Frasor – TOR – 4.43 ERA, 86% IRS (14/12)
Jamie Walker – BAL – 3.43 ERA, 85% IRS (13/11)
Scott Schoeneweis – NYM – 5.95 ERA, 85% IRS (13/11)
J. C. Romero – BOS – 3.38 ERA, 85% IRS (13/11)
Brian Tallet – TOR – 2.01 ERA, 85% IRS (13/11)
Brandon Morrow – SEA – 1.74 ERA, 85% IRS (13/11)
Pedro Feliciano – NYM – 0.90 ERA, 84% IRS (19/16)
Jonah Bayliss – PIT – 6.60 ERA, 83% IRS (24/20)
Jon Coutlangus – CIN – 5.12 ERA, 83% IRS (18/15)
Kevin Gregg – FLA – 1.93 ERA, 83% IRS (12/10)
Frank Francisco – TEX – 3.10 ERA, 83% IRS (12/10)
Geoff Geary – PHI – 3.58 ERA, 83% IRS (29/24)
Will Ohman – CHC – 5.27 ERA, 83% IRS (23/19)
Chad Paronto – ATL – 7.47 ERA, 82% IRS (17/14)
Javier Lopez – BAL – 3.46 ERA, 82% IRS (17/14)
Brian Shouse – MIL – 4.38 ERA, 82% IRS (33/27)
Jesus Colome – WAS – 2.43 ERA, 82% IRS (11/9)
Heath Bell – SD – 1.08 ERA, 82% IRS (11/9)
Gary Glover – TB – 4.97 ERA, 81% IRS (16/13)
Chad Bradford – BAL – 2.35 ERA, 80% IRS (20/16)

That’s the list up to 80% effectiveness.
Not a lot of household names up there, but a lot of effective relievers.
And, yes, Betancourt is tops in MLB.

But wait, you say, Betancourt is the only Indian on the list. And here lies the problem with the Indians’ current bullpen.

The numbers for the rest of the Tribe bullpen:
Rafael Perez – CLE – 0.00 ERA, 100% IRS (2/2)
Joe Borowski – CLE – 7.29 ERA, 83% IRS (6/5)
Tom Mastny – CLE – 5.01 ERA, 67% IRS (15/10)
Roberto Hernandez – CLE – 6.23 ERA, 67% IRS (12/8)
Aaron Fultz – CLE – 1.69 ERA, 66% IRS (32/21)
Fernando Cabrera – CLE – 5.40 ERA, 25% IRS (4/1)

That’s right, despite a 1.69 ERA, Aaron Fultz has allowed about 1/3 of his inherited runners to score, which is not a great number when you’re the match-up lefty on a team and generally don’t come in at the beginning of an inning.

Mastny, Hernandez, and Fultz all rank in the 70’s on the list, compared to the rest of MLB, when it comes to effectiveness when entering a game with runners on base against other relievers who have 10 or more inherited runners on the season. Perez, obviously, has been up for too short of a time to get a real read on his effectiveness, but the early returns look good.
You don’t want to know where Cabrera falls – it’s obvious to the naked eye.

The beauty of the IRS % is it quantifies a reliever’s effectiveness when thrown into a tough spot. Of course, some pitchers come in to start an inning (set-up guys and closers), but some pitchers that you would imagine would be overall effective relievers are, in fact, much worse with Inherited Runners:

Scot Shields – LAA – 2.76 ERA, 47% IRS (15/7)

So, how does a team like the Indians (whose overall IRS % sits at 72%, which means that basically 1 of 4 inherited runners score) do with this statistic. A combination of ERA and IRS % can be used to show a pitcher’s effectiveness to start an inning and also with runners on. But it also gives them an idea of who should enter games with runners on base and whether a reliever is better at starting an inning (as Jason Dangerously famously was) or has the intestinal fortitude to douse the flames of an already burning fire.

What these numbers show is that the Indians need to give Rafael Perez some of the opportunities being given to Aaron Fultz as the match-up lefty as Fultz (with his low ERA and high IRS % may be more suited to start an inning). It also backs up the obvious fact that Hernandez and Cabrera have become complete liabilities in the bullpen and that a move is going to have to be made soon before Wedge taxes the rest of his bullpen (Betancourt and even Mastny) to stay away from those two in ANY situations.

It essentially shows that the Indians are two and maybe even three effective relievers away from having a bullpen that is truly effective in all aspects of their responsibilities. Whether the relievers that can improve this percentage of inherited runners are within the organization (Perez, Eddie Mujica, or Juan Lara) or need to be found elsewhere in MLB is what faces the Indians at this point is what the Indians need to determine to keep the team on top of the AL Central through the long summer ahead.