Sports Reference Blog

2019 WAR Update

Posted by Alex Bonilla on March 21, 2019

As we approach the beginning of the 2019 season, we have made some updates to our Wins Above Replacement calculations.  You may notice some small changes to figures as you browse the site. As always, you can find full details on how we calculate WAR here.


Last season, the Tampa Bay Rays popularized the concept of the opener, where the first pitcher of the game is expected to pitch considerably less than a typical starting pitcher.  The opener is followed by a “headliner” or “bulk guy,” who enters the game after the opener but takes on responsibilities similar to a traditional starting pitcher. The Rays found success with this approach, and several other teams followed suit.

Our Wins Above Replacement calculation treats starting pitchers and relief pitchers differently, since relief pitchers have much lower ERAs than starters.  The opener strategy throws a wrinkle into this, since the opener is not expected to go deep into the game and the headliner is, so we have a starting pitcher who is behaving more like a relief pitcher and vice versa.

Tom Tango posted some thoughts on this last year, and the discussion in the comments of that post produced a working definition for the opener:

  1. Determine if we have an opener.  This pitcher must start the game and have either at most 2 innings pitched (6 outs), or at most 9 batters faced.
  2. Determine if we have a headliner. This pitcher must meet two criteria:
  3. Length of appearanceAt least 4 innings pitched (12 outs), or at least 18 batters faced
  4. Order of appearanceThey are the first reliever, OR they are the second reliever, but the first reliever entered mid-inning, and the second reliever started the following inning


If both these pitchers exist, then we have a game with an opener and a headliner.  Both pitchers must exist; you cannot have an opener without a headliner, and vice versa.

Using this definition, we have updated our WAR calculation to treat openers like relievers and headliners like starters.  This change has been applied to all seasons since 1960, the first year we apply a starter/reliever adjustment.

Ryan Yarbrough, the Rays’ most frequent headliner, is an instructive case.  He pitched 38 games and 147.1 innings, but started just 6 times.  By the above definition, 16 of his relief appearances were as a headliner.  Prior to this adjustment, the Rays’ rookie had 0.9 WAR for 2018. After the adjustment, Yarbrough has 1.5 WAR.  The new calculation recognizes that Yarbrough is behaving more like a traditional starting pitcher, and holds his performance to the same standard it would if Yarbrough had started those games.

Park Factors

Park factors for recent seasons have been re-computed to be three-year rolling averages. For instance, 2017 Park Factors now encompass 2016-2018. This is something that needs to be done each year when the season ends.

Catcher Defense Prior to 1953

With help from Sean Smith of (and of an unnamed team front office) and baserunning statistics from Pete Palmer, we now have incorporated catcher defense for the years 1890 through 1952 based on stolen bases, caught stealing, errors, passed balls, and, from 1925 on, wild pitches.  Prior to this update, these players’ defensive abilities were judged only based on errors and passed balls.

Duke Farrell is a particularly noteworthy beneficiary of this change.  His career WAR rises by nearly 8 wins, because he played in an era (1888-1905) with a lot of stolen base attempts and did a better job of throwing out runners than his contemporaries.

This change also impacts pitchers’ WAR figures, since we have more information about the quality of defenses to take into account.  For instance, Jack Taylor and Kid Nichols of the 1904 Cardinals see their WAR numbers rise by more than a win each after accounting for the fact that their catchers threw out fewer runners than the rest of the league.  Indeed, the Cardinals’ primary backstop Mike Grady saw his WAR drop by two wins with this update.

On the flipside, legendary pitcher Cy Young loses more than 4 wins over his career after accounting for the above-average work his teammates did behind the plate throughout his career.

We’ve highlighted some of the more extreme changes here, but to see full lists of the largest changes to season and career WAR totals, please see the spreadsheet here.


12 Responses to “2019 WAR Update”

  1. Jackson M Says:

    What is the reasoning between differentiating between starters and relievers for WAR rather than just going by TTO or IP/appearance or something similar?

  2. Random Awesomeness (part 2019.4) | The Writer's Journey Says:

    […] 2019 WAR Update [Sports Reference] […]

  3. Eric Chalek Says:

    Any chance we will also soon be getting a historical update that incorporates all the Retrosheet data that’s come out the last three years?

  4. Tom Says:

    Eric, I've been looking forward to that too. I keep checking the Play Index hoping it gets updated back to 1906. Hopefully those updates will happen soon.

  5. Johnny Twisto Says:

    Won't this change in handling openers/headliners also affect regular SP who get bombed and pulled early, and long relievers brought in to sop up innings?

  6. What I’m Watching in 2019 | the Hall of Miller and Eric Says:

    […] bit more under-the-radar than the framing update at Fangraphs is the annual WAR update over at Baseball Reference. They’ve made some tweaks to catcher defense prior to 1953, so that […]

  7. Framing the Hall of Fame Cases for Martin and McCann | The Baseball Bat Reviews Blog Says:

    […] it’s worth noting that just as we introduced our framing stats, Baseball-Reference published an update to its catcher defensive numbers and WAR from the 1890-1952 period. Prior to the update, catcher […]

  8. Tim Lemke Says:

    I am confused as to why you say an opener and a headline must co-exist. There could easily be scenarios where someone starts a game and has two or fewer innings pitched and no pitcher after that throws four innings.

  9. Tom Says:

    @ Tim Lemke-

    I think they worded that paragraph in a stupid, confusing way. It basically is saying "if both an Opener and a Headliner exist, then both an Opener and a Headliner must exist". It is unneccessary and redundant to include that as part of the definition, and they way they worded it is doubly confusing.

  10. charlieo Says:

    [...]For instance, 2017 Park Factors now encompass 2016-2018. This is something that needs to be done each year when the season ends.--------------------------------------------------------------------------------------

    From reading this, it would appear that the Park Factor for 2018 cannot be calculated because the 2019 season has not yet ended..

  11. Mike Lynch Says:

    It is calculated, but it is not yet finalized. That is correct

  12. Christian Says:

    "I am confused as to why you say an opener and a headline must co-exist. There could easily be scenarios where someone starts a game and has two or fewer innings pitched and no pitcher after that throws four innings."

    That was my question as well. In a situation like that, would the first pitcher be treated as a starter, and all the rest of the pitchers as relievers? Or would they all be treated like relievers?