The Rockies’ bullpen troubles are the trouble with bullpens

The 2016 Rockies’ bullpen has been terrible by every measure. Everything from the context neutral ERA to the context reliant Win Probability Added (WPA) shows that the committee has been one of the worst in baseball in 2016, as well as one of the worst in recent memory. Bryan Kilpatrick covered the Rockies’ woes in terms of WPA recently (and also defined the statistic for those unfamiliar). The bullpen’s WPA is the most damning because it shows how bad the relievers have performed in high leverage situations, which in turn highlights how many winnable games the bullpen has cost the Rockies. That, and their current WPA is the 13^th worst mark since 2002; that’s also pretty damning.

But that’s fine. We’re not worried about 2016, which has been lost for a while now. We’re concerned with 2017, and we’re concerned with the Rockies improving the biggest hole on the team. Because the Rockies currently have the 13^th worst bullpen WPA since 2002, there have been 12 teams with worse seasons from the bullpen. Those teams also fielded bullpens the following year, and a lot of them were good.

Examining the most dramatic bullpen turnaround, the 2007 Devil Rays and the 2008 Rays, shows us one way that a bullpen went from awful to excellent in the span of a season.

In 2007, the Devil Rays’ bullpen had the worst WPA in baseball at -8.61. In fact, this was the worst bullpen WPA since 2002. The Rockies’ 2016 bullpen would need to blow every game of the season to reach the 2007 Devil Rays’ level of unclutchness. The bullpen’s poor season was reflected in the team’s 66-96 record. In 2008, Tampa Bay improved by 31 wins to finish 97-65, win the American League East, as well as the American League. And this reversal, too, was evident in the bullpen’s WPA. It went from -8.61 in 2007 to 9.26 in 2008. The committee held leads and excelled in high leverage situations.

They did it by adding a reliable free agent, transitioning a struggling starter to the bullpen, and getting a bounce-back year from one of their returnees. First, they signed Troy Percival to be their closer, who was 38 at the time, to a two-year contract worth about $8.5 million. That’s the role he played, even though he didn’t perform very well. He posted a 4.53 ERA, but he saved 28 games out of 32 chances. His 0.52 WPA was good in that it was positive, but it was only sixth best from the bullpen.

The most significant contributors to the 2008 turnaround were two players who were already on the team. Grant Balfour joined Tampa Bay in the middle of 2007, when they traded Seth McClung to Milwaukee for him. In 22 innings in 2007 in Tampa Bay, he posted a 6.14 ERA and had a WPA of -0.61. His primary issue was walks, but his strength was the ability to strike batters out. In 2008, he reduced walks and upped his strikeout rate. The result was a 1.54 ERA and a second-best on the team 2.71 WPA.

The pitcher who led the team in WPA was also on the team already. In 2007, left-hander JP Howell started ten games for the Devil Rays. The 2008 Rays transitioned him to the bullpen, where he pitched anywhere from 0.1 to three innings per appearance. Howell finished the season with 89 innings pitched, a 2.22 ERA, and a team-leading 3.33 WPA. He excelled in high-leverage situations and played a significant role in the Rays’ success.

These three players were key, but there was another returning reliever who tells us something about major-league bullpens. After Percival, Dan Wheeler picked up the second most saves for the team, with 13. Wheeler was on the 2007 club. In these two seasons, he improved his WPA from -0.72 to 1.04. What’s most revealing about Wheeler is that his underlying statistics from 2007 to 2008 didn’t improve. In fact, his walk and strikeout rates got worse. And yet, his ERA fell from 5.30 in 2007 to 3.12 in 2008. A great deal of that is owed to his BABIP against plummeting from .317 to .190. Many factors contribute to fluctuations in BABIP, and some of them have to do with skill; however, when walk and strikeout rates get worse and a BABIP against falls over .100 points, it’s due to luck.

If we think of what the 2017 Rockies could do with the bullpen in terms of what Tampa Bay did from 2007-2008, this is what we would get: sign a free agent like Brad Ziegler to be Troy Percival and close games, use Chris Rusin as a left-handed multi-inning reliever in the mold of JP Howell, and deploy one or both of Adam Ottavino and Carlos Estevez in high-leverage situations to play Grant Balfour. Tampa Bay had other returnees who performed well, such as Scot Dohmann, and there were other additions who played a role, such as Jason Hammel. Still, Tampa Bay didn’t do much in the way of revamping the bullpen to turn it from a disaster to spectacular. Their best relievers were already on the team, and the biggest difference is that they collectively performed well in high leverage situations. Different decisions form the dugout could have contributed to the improvement (though Joe Maddon managed both teams), and luck almost certainly played a role.

There are additional success stories found in the other 12 bullpens who have posted WPAs worse than the 2016 Rockies. The 2011 Diamondbacks’ bullpen was the worst in the league, and in 2010 they rebounded to post a respectable 2.99 WPA, largely on the broad shoulders of free agent JJ Putz. But other bullpens improved their WPA without much improvement in record (the 2006-2007 Royals). Others improved their WPA, still ended up in the negative, and still improved their overall team record (the 2002-2003 Royals). And yet others were carried by a single reliever who went from pretty good to outstanding (Rafael Betancourt for the 2006-2007 Indians.).

This offseason will bring a lot of conversation about what the Rockies should do to improve the bullpen. In terms of WPA, the Rockies bullpen will almost certainly be better in 2017, but that’s only because it was historically bad in 2016. History indicates that they could find success simply by making a few tweaks to existing personnel. But for them to turn from awful to well and truly good, there’s no formula for them to follow. That’s both exciting and stressful—a bit like watching a reliever in a high-leverage situation.