| 12 October 2011
The Diamondbacks improved by 29 games from 2010 to 2011, and the biggest area of improvement was in the bullpen. The 2010 bullpen was one of the worst in baseball history, but the 2011 version actually was a strength for the team. As a group, the 2011 bullpen allowed 100 fewer runs than the 2010 group, in the same number of innings, bringing the ERA down from 5.74 to 3.71.
| Year | W | L | ERA | Saves | BS | IP | H | ER | K/9 | BB/9 | HR/9 | BABIP |
| 2010 - Pen | 16 | 32 | 5.74 | 35 | 24 | 439.0 | 485 | 280 | 6.79 | 4.59 | 1.27 | .314 |
| 2011 - Pen | 23 | 14 | 3.71 | 58 | 13 | 439.1 | 413 | 181 | 7.75 | 3.40 | 0.80 | .295 |
The improvement can be seen in every statistical category - more wins, fewer losses, more saves, fewer blown saves, more strikeouts, fewer walks, etc. Of course, the biggest keys for the 2011 bullpen were the new members, especially new closer J.J. Putz and setup man David Hernandez. But really, the improvements in the pen were across the board - almost every member made a positive contribution, and if they didn't, they didn't stick around for long (Vasquez, Gutierrez, Heilman). (bWAR is Wins Above Replacement from Baseball-Reference.com)
| Pitcher - 2011 | IP | ERA | bWAR | Saves+Holds | Blown Saves/Holds |
| J.J. Putz | 58.0 | 2.17 | 2.1 | 45 | 4 |
| David Hernandez | 69.1 | 3.38 | 1.1 | 34 | 3 |
| Joe Paterson | 34.0 | 2.91 | 0.7 | 10 | 0 |
| Bryan Shaw | 28.1 | 2.54 | 0.5 | 9 | 0 |
| Brad Ziegler | 20.2 | 1.74 | 0.3 | 4 | 0 |
| Josh Collmenter | 14.0 | 1.29 | 0.3 | 0 | 0 |
| Alberto Castillo | 11.2 | 2.31 | 0.3 | 3 | 0 |
| Micah Owings | 42.2 | 3.59 | 0.2 | 3 | 0 |
| Sam Demel | 25.2 | 4.21 | 0.0 | 6 | 1 |
| Zach Duke | 25.2 | 3.86 | 0.0 | 1 | 0 |
| Esmerling Vasquez | 30.1 | 4.15 | -0.1 | 6 | 2 |
| Juan Gutierrez | 18.1 | 5.40 | -0.6 | 2 | 1 |
| Aaron Heilman | 35.1 | 6.88 | -0.9 | 5 | 1 |
The newcomers to the bullpen included one medium-priced free agent signee (Putz), two players acquired in trades (Hernandez, Ziegler), a Rule 5 pickup (Paterson), two rookies (Collmenter, Shaw), and two free agents signed to minor league contracts (Owings, Castillo).
For comparison, here is the same table for the 2010 bullpen. Not a single regular member of this group had a positive WAR for the year - only part-timers Carrasco and Rosa managed to be above zero.
| Pitcher - 2010 | IP | ERA | bWAR | Saves+Holds | Blown Saves/Holds |
| D.J. Carrasco | 22.2 | 3.18 | 0.3 | 2 | 1 |
| Carlos Rosa | 20.0 | 4.50 | 0.1 | 1 | 1 |
| Aaron Heilman | 72.0 | 4.50 | 0.0 | 18 | 8 |
| Blaine Boyer | 57.0 | 4.26 | -0.2 | 5 | 4 |
| Jordan Norberto | 20.0 | 5.85 | -0.2 | 3 | 1 |
| Esmerling Vasquez | 53.2 | 5.20 | -0.3 | 6 | 2 |
| Juan Gutierrez | 56.2 | 5.08 | -0.4 | 23 | 2 |
| Leo Rosales | 16.1 | 7.16 | -0.5 | 2 | 0 |
| Sam Demel | 37.0 | 5.35 | -0.7 | 6 | 0 |
| Bob Howry | 14.1 | 10.67 | -0.7 | 1 | 1 |
| Chad Qualls | 38.0 | 8.29 | -2.5 | 15 | 4 |
In addition to the improved numbers for Saves and Holds, the 2011 bullpen also did an excellent job of preventing Inhertited Runners from scoring. Only 31% of inherited runners scored in 2011, led by Bryan Shaw (17%) and Brad Ziegler (19%). This was a huge improvement from 2010, when 41% of inherited runners scored, ranking last in the NL.
Conclusions
The bullpen changed from a huge liability in 2010 to a huge asset in 2011. The group's ERA dropped by over 2 runs per game, and the Save Percentage jumped from 59% to 82%. The eight highest performing members of the bullpen were all new additions to the team, with Putz and Hernandez clearly huge factors in the club's turnaround. The good news for the future is that Putz, Hernandez, Paterson, and Shaw will all be back for the 2012 campaign. Ziegler is arbitration-eligible and could return, and Owings, Castillo, and Demel will be returning to battle for spots along with rookies like Ryan Cook. The bullpen should continue to be an asset in 2012.
 |
Follow DV on Twitter |  |
Buy DV D'Backs Tickets |
