Is the Phillies’ Bullpen Just Bad?

In the comment’s of Paul’s post about Antonio Bastardo, AGH asked this question:

The Phillies have allowed the third most two-out runs in all of baseball. The pitching staff’s two-out ERA is also third worst (5.48), better only than the Rockies and the Indians.

Certainly injuries/lack of talent plays a part, but how much bad batted ball luck is involved in a stat like this? Is this the sort of stat that typically regresses to the mean?

It is an interesting question and one I think is worth addressing in its own post.

Simply put, there is very little correlation from one year to the next when it comes to the bullpen. The correlation coefficient for runs allowed by each team’s bullpen from 2011 to 2012 is 0.169, which is weak. There a lot of reasons why a split that drills down to a) relievers only b) with only two outs c) in only one year isn’t reliable.

Sample size: National League relievers so far this year have faced 24,410 batters with two outs out of 75,284 total batters, or 32.4%. So you’re cutting your sample size by two-thirds right from the start. Each team has had its bullpen pitch with two outs between 1,486 and 1,607 times. Then consider that each team has used at minimum 10 relievers. In reality, we’re talking about individual sample sizes under 100 PA — often way under — for each reliever.  Additionally, teams don’t use their relievers uniformly. For example, Jonathan Papelbon has logged over 50 innings while Raul Valdes is only at 27.2. Furthermore, some relievers are used to get only one out, most notably lefty specialists, so they either never pitch with 2 outs or only do so in a favorable match-up. As a result, your samples are heavily influenced by a lot of outside factors, even beyond what I have listed here.

Batted ball luck: Yep, BABIP plays a huge role in the success or failure of every bullpen. Some years, like the 2008 Phillies, almost everything goes right. Other years, like this year, everything goes completely wrong. From 2011 to 2012, there was actually a negative correlation in aggregate bullpen BABIP, -.153, still weak. But it tells us that BABIP essentially regresses to the mean the next year. In other words, if your BABIP is above-average in one year, it is likely to drop in the next year, and vice versa. Phillies relievers have an aggregate .306 BABIP but their true talent level may lie somewhere in the .290′s since they are so good at missing bats — their collective 24.5% strikeout rate is fourth-best in all of baseball. It is worth recognizing that the Phillies have had an astoundingly bad year on defense, especially with the Chase Utley, Freddy Galvis, and Placido Polanco injuries.

Turnover: Relievers, particularly non-closers, have notoriously bad job security. Teams are happy to shuffle younger arms between the Major and Minor Leagues at a moment’s notice, and often sign the older players to short-term deals. While GM Ruben Amaro brought some familiar faces back, the Phillies did say goodbye to Ryan Madson, Danys Baez, Brad Lidge, J.C. Romero, and Mike Zagurski, among others. There is a difference between that group of players — mostly veterans — and Michael Schwimer, Joe Savery, Jake Diekman, and B.J. Rosenberg — all young players — and it affects the stats we use to judge bullpen performance.

Injuries: The Phillies have been bitten badly by the injury bug as they’ve seen Jose Contreras, David Herndon, and Michael Stutes hit the disabled list. Pitchers, more than position players, are prone to injury, so they may not make the same impact from one year to the next. Additionally, the health of the Phillies’ starting rotation also affects how the bullpen is used. Cliff Lee and Roy Halladay have both been injured at times this year, forcing Charlie Manuel to use a sub-par replacement (Kyle Kendrick) and rely on his bullpen more.

Trades: This is pretty self-explanatory. In the bullpen, the Phillies have Josh Lindblom and Jeremy Horst, both acquired in trades — Lindblom in the Shane Victorino deal and Horst in the Wilson Valdez trade. David Herndon was also acquired in the Rule-5 draft. This is just another way new faces are brought into the mix and familiar ones can drift away.

It’s easy to look at all of the awful bullpen stats and conclude that the relievers are collectively awful and that the Phillies need to make a significant change, but the reality is the crew they have assembled is actually decent. They have a 4.54 ERA but a 3.95 xFIP, the disparity due in part to an NL-high 39.6% fly ball rate and an above-average 12% HR/FB rate. Don’t forget that 11 of the 40 home runs Phillies relievers have allowed came from Chad Qualls and Brian Sanches, both no longer with the team. Lindblom has allowed three homers in eight innings of work, but he is having a bad year in that regard and figures to  be better next year. The fact is that bullpens in general, and the individual pitchers that are part of them, are volatile by nature. The 2012 Phillies simply had a bad roll of the dice in many ways when it came to the bullpen, but it should be noticeably better next year even if they do nothing.