Let’s start off by acknowledging how great Putz has been over the last two seasons. He’s been lights out for the majority of his time with the Diamondbacks despite a couple of rough patches. This April was one such rough patch. He’s gotten off to slow starts before and has seemingly always got rolling as the season progresses.

Perhaps JJ was about to turn it around, but we can’t ignore the fact that he’s 36 and has thrown a lot of

splitters. Those have been known to put heavy pressure on the elbow and the splitter has long been deemed one of baseball’s most unsafe pitches. In fact, some organizations even refuse to teach it to their minor leaguers.

JJ Putz leaves the game against the Dodgers. IMAGE: Gary A. Vasquez-USA TODAY Sports

Now that JJ has been diagnosed with “elbow tightness,” we have to wonder if the innings, the age and all those splitters have come back to take their toll. As Ken Rosenthal reported this morning, Putz has a sprained ligament, strained flexor muscle and an irritated nerve in that elbow. Apparently Putz will try to rehab his way back into the lineup, but it appears that surgery is looming should the rehab prove ineffective. In other words, JJ’s future as a Diamondback is in serious jeopardy and we shouldn’t assume we’ll ever see him regain his form again. Could he come back the same? Maybe, but at his age and given the severity of the injury, I’m not betting on it.

Enter Heath Bell. I, for one, did a lot of head scratching when Arizona acquired him from Miami. I was critical of Kevin Towers for taking on Bell’s contract given his age and ineffectiveness. Heath had lost velocity and his strikeout rates were were trending down, plus he didn’t have Petco Park to suppress run scoring. As we all know, the ball can fly in the desert, much more so than in his golden days with the Padres.

Bell has looked better in the desert thus far, though,  especially compared to his time as a Marlin. His velocity is slightly up, the strikeouts are way up and, most importantly, the walks are way down. His 4.40 ERA is misleading as he’s been unlucky thus far (.417 BABIP) and his FIP of 2.64 reflects this. I’d expect the his K/9 to fall a little bit and his BB/9 to rise some, but even with a little regression, he still appears to be capable of being effective as a closer.

To dig a little deeper, let’s take a look at the projections of both players going forward. Here are the ZiPS Rest of Season (ROS) projections for both pitchers: 

As you can see, the projections see them as different pitchers, but both are on the same path in terms of value. Putz and Bell would be set to accumulate 0.6 WAR over the rest of the season, they would just do so in different ways. Putz boasts a better K/BB ratio, but Bell is better at keeping the ball in the yard. Both have similar career groundball rates and both have experience closing out games. If Bell can keep his head and avoid getting rattled if and when he blows a save, there is reason to believe that we should see no major drop-off in the ninth.

Heath Bell notches a save for the Dbacks. IMAGE: Kirby Lee-USA TODAY Sports

There’s been some clamoring for David Hernandez to become the closer, but Gibby clearly prefers a veteran in that role. Hernandez is likely the future, but Bell should be able to keep him from taking over this season. The bullpen is old overall and there is sure to be a changing of the guard in the near future, as neither Bell nor Putz are long-term solutions at this point in their careers.

For now, however, we’re going to have to roll the dice with Heath Bell, but there’s hope that he can keep the Dbacks in the thick of the NL West race.

In a corresponding move, the D’backs have activated top prospect Didi Gregoriusto replace Hill on the roster. Nick Piecoro, of Azcentral Sports, reported that manager Kirk Gibson expects Hill to miss 4-6 weeks with the injury.

Image: Jake Roth-USA TODAY Sports

Hill was originally diagnosed with a bone bruise after the hit-by-pitch, missing the next two games before pinch hitting on April 13 and starting Sunday’s game but only lasting four innings. A sore wrist was said to be the culprit for that early removal.

Gregorius was acquired in the trade that sent top pitching prospect Trevor Bauer to Cleveland. Gregorius is known for an outstanding glove at shortstop that perhaps outshines his bat.

Though, Gregorius is off to a hot start in hitting-heaven triple-A Reno. He’s hitting .387 with a .424 OBP and a .645 slugging, scoring seven times with two home runs. Gregorius has been recovering from an injury of his own, an elbow injury that prevented him from playing the field until yesterday.

It’s unclear if Didi will play everyday for the D’backs or even where he will play. The D’backs have several options: sliding Gregorius into second to replace Hill, moving Cliff Pennington to second and Gregorius will take over short, or even moving Martin Prado to second and having Eric Chavez in the everyday lineup.

Hill was hitting .306 with two home runs and getting on base at a .405 clip for the D’backs in 42 plate appearances this season.

Sep 20, 2012; Chicago, IL, USA; Chicago Cubs second baseman Darwin Barney (15) is forced out by Cincinnati Reds shortstop Didi Gregorius during the ninth inning at Wrigley Field. The Reds won 5-3. Mandatory Credit: Jerry Lai-USA TODAY Sports

Gregorius was examined by the D’backs team physician, Dr. Michael Lee, who suggested that he limit all activity for four weeks after feeling pain during a January throwing session. According to the Bickley and MJ show on Xtra Sports 910 in Phoenix, the problem is with the ulnar collateral ligament in Gregorius’ throwing elbow and while surgery will not be ordered on the elbow now, that it may be an option if it doesn’t heal in the future.

GM Kevin Towers feels that this will only be a temporary delay for the Dutch product and expects him to begin playing games towards the end of Spring Training if all goes well with a throwing program that will be implemented during the beginning of Spring Training.

Veterans Willie Bloomquist and Cliff Pennington will attempt to take advantage of Gregorius’ absence as they will split most of the time at shortstop during the time that the slick fielding shortstop will be sidelined.