David Hernandez pitches in the eighth inning against the Los Angeles Dodgers. IMAGE: Gary A. Vasquez-USA TODAY Sports

So what’s been behind the turnaround? It appears that he’s altered his pitch selection yet again and we can’t argue with the results. Over his last six outings, he’s using the four-seam fastball more, the two-seamer less and he’s hasn’t thrown a changeup over his last five appearances. Looking at his previous usage patterns, this is a clear shift.

Perhaps what’s stood out more than anything else is David’s efficient use of the curveball. He’s not necessarily using it more often, but he’s using it more effectively. Rather than using the two-seamer to try and set up the changeup, he appears to be using the four-seamer to set up the curveball. This is more similar to his strategy of the past and the results have been very good. Hernandez throws his power curve from the same arm-slot as his fastball, making it difficult for hitters to pick up until it dives out of the zone or simply become unhittable.

In his last six appearances, David has thrown the curve 33 times with 25 going for strikes (76%) and 8 for balls (24%). He’s allowed two singles while recording seven outs on the pitch. Better yet, he’s recorded five strikeouts via the curveball over that short span. It’s back to being an out pitch for him and that should make him much, much more lethal on opposing hitters.

Case in point: on the 14^th, against the Braves, he struck out Brian McCann by alternating between his fastball and curveball, throwing all three curves for strikes and getting McCann to chase a curve for strike three. The next batter was Justin Upton, who the had gone 4-5 the day before, and Hernandez threw him three curveballs in a row, all three for strikes, and froze Upton with a curve on the outside corner for strike three to end the 8^thand protect Patrick Corbin’s stellar performance.

Hernandez appears to have ironed out his approach and is executing his pitches. If it seems like we’ve been seeing the David Hernandez of old lately, it’s because he pitching much more like he has in the past. He’s successfully turning leads over to Heath Bell to finish the job and his stability means a lot for the bullpen. There was nothing but dismay two weeks ago when the ‘pen was getting crushed. It’s far from perfect, but Hernandez’ stability is a good sign for the Diamondbacks moving forward.

*Pitch F/X data accessed 5/16 from mlb.com and fangraphs.com 

Is Cole Hamels just getting unlucky? Or is it something else?

Unlucky.  Cole has had plenty of issues with run support before, and with bad luck, so combined with a slow start, he’s been pretty ineffective.  Especially for a guy we made such a big deal about signing for six more years.

The stuff’s in there.  We could just really use some more blatant examples of it recently, with so much less potent of a rotation backing him up.

Should Ryan Howard scare opposing fans anymore?

Absolutely.  Have you seen that contract?  They tell stories about it around the bonfire at training camp.

What’s the upside of this team? The downside?

The upside is that we have Cole locked up, Freddy Galvis is youthful and full of vigor, Chase seems to be hitting okay, and Cliff Lee is here.  The downside is that Chooch, Doc, and Chase are all up for reassignment, the team in general is not very good, Ben Revere looks more and more like a complete bust, the parts of the bullpen that work are wastes of money if the other parts of the bullpen that aren’t working continue to not work, and everybody’s only getting older.

Also, it’s all Charlie Manuel or Ruben Amaro‘s fault, depending on the day.

Why do the Phillies’ brass seem perplexed as to why their lineup doesn’t take walks? 

Related, have they heard of baseball reference before?

I’d say probably no.  Ruben Amaro shows a staggering absence of intelligence at times, for a guy who seems to have it all figured out.  His lack of belief in walks and the organizations disbelief in modern stats is sickening at times, and probably why some players (AHEM Dom Brown) have been mishandled in the recent past.

How mad are you at Kevin Towers for giving your divisional rival a christmas present of Justin Upton?

I would be pretty mad, but honestly, we’ve got about 1,000 problems to worry about before we can fathom taking on the Braves, let alone Upton.  Then again, he is an individual example of the Braves as a whole – lot of home runs, lot of strike outs.  They’re gonna hack.  And it’s already bringing them back down to earth.

Is Michael Young as classy as everyone says he is?

I’ll say sure.  But I was never worried about that.

If he could convince a ground ball to hop into his glove using that keen sense of clubhouse leadership, that’d be great.  But they’re usually moving too fast.

His questions and my answers:

So is Ian Kennedy going to be a problem or can we depend on his location sputtering out again?

This, sadly, is what we can expect from Kennedy. He’s been pretty mediocre for the past 12 months. And that’s mostly been tied to his lack of command with the fastball. While he isn’t walking a ton of people, he also grooves way too many to be effective.

J.J. Putz has decided to take some time off to be injured.  How reliable is the Dbacks bullpen now?  Express in terms of Chad Durbins.

I believe I saw that Putz was heading to the Dominican for a couple of months. I can’t confirm that, but nonetheless, it’s a weird time to take a vaca. However, I believe the bullpen should still be (just a tad) better than one Chad Durbin. David Hernandez has had a couple of shaky outings but has been pretty good and should get better. And outside of Heath Bell‘s first appearance, he’s been (stunningly) pretty good. Combined with Brad Ziegler and Matt Reynolds, the pen should be in decent shape still.

Is it correct to say Paul Goldschmidt is “becoming a star?”  And if so, what kind of a star; one that shines brightly for a long time, or when that grows too big and kills a lot of people?

He’s a star that’s going to kill a lot of people. Just not in the way you were meaning. I think he singlehandedly murdered Tim Lincecum‘s career and is in the process of burying the corpse of Chris Capuano now. He’s been a revelation. He’s improved his walk and strikeout rate, chase percentage and his fielding immensely over the past couple of seasons. He’s approaching top three first baseman in the league quickly.

Lie to me.  What do you think of this team without Roy Halladay?

They’re great. One of the best staffs that can’t pitch and one of the best lineups that can’t walk (or score) I’ve ever seen.

Is there a young prospect with a better name than “Didi Gregorius” in baseball right now?

Xander Bogaerts is a pretty dang good name. Adeiny Hechavarria? Basically all shortstops in baseball it looks like.

The bulk of the struggles have largely been limited to those in high-leverage situations, notably JJ Putz and David Hernandez. I was curious to know if these guys were failing to perform like they have in the past or whether this was just a blip on the radar that could be attributed to bad luck and small sample sizes. I wanted to know if this was something that we should be concerned about or whether we could reasonably expect this difficult stretch to pass. After all, they wouldn’t be the first major league pitchers to get off to a slow start, right?

Digging through their performances, pitch-by-pitch, a few things jumped out at me. We’ll take a look at both Putz and Hernandez individually to see just how they’ve been getting exposed.

Arizona Diamondbacks relief pitcher J.J. Putz. IMAGE: Ed Szczepanski – USA Today Sports

It’s no secret that JJ has been excellent for the Dbacks over the last two seasons. He’s built that success largely by doing three things: striking out a lot of batters, issuing very few walks and limiting the number of homeruns he’s allowed. In 2013, he’s still recording a lot of strikeouts (12.8 K/9) but the walks are killing him. He hasn’t posted a walk rate like his current one (4.97 BB/9) since 2009 with the Mets. He’s walked less than two batters per nine innings in each of the last two years, so this current spike is unexpected. Making matters worse, JJ has already surrendered three homeruns through 12.2 innings in 2013 after allowing only four all of last year (54.1 IP) and only four in 2011 (58 IP). If there’s anything we know about pitching, it’s that walks and homeruns are a good recipe for disaster. So far, JJ is way above his norms in both categories.

What’s leading to these issues? Looking at Pitch F/X data, it’s clear that his velocity is down throughout his arsenal. We don’t know if this is simply a matter of him building up early season arm strength or if he simply is losing velocity. At 36-years old, a drop in velocity wouldn’t be surprising. He’s also altered his offerings to hitters, throwing his fastball less often and using his slider more. The slider has been simply average so far and his fastball hasn’t been nearly as effective as usual. But Putz is most notable for his splitter. When he commands the hammer, it’s lights out for hitters. Unfortunately, the splitter is notorious for being one of the most difficult pitches to command in baseball. So far, JJ is having trouble with the pitch and it’s getting crushed. Because of his struggles with throwing consistent strikes, hitters are taking more and chasing less, forcing him to come over the plate and risk getting hit hard. And that’s just what’s happened.

David Hernandez’ struggles have also seemingly come out of nowhere. His recipe for success in the past has been high strikeout rates and not giving up the long ball. Never a control artist, Hernandez is currently right on par with his career walk rate (3.95 BB/9), but his strikeouts are down from last year. More importantly, he’s been burned by the homerun, as opponents have already put four offerings over the fence this year (13.2 IP). He allowed only four dingers in each of the last two years, so his current homerun rate is surprising. Given his propensity to walk hitters, the homeruns are painful. For example, on May 1^st, he entered the 8^th inning protecting a one-run lead. Hernandez walked two hitters before giving up his latest long ball, a three-run heart-breaker that gave the rival Giants a lead they wouldn’t surrender.

Arizona Diamondbacks relief pitcher David Hernandez. IMAGE: Ed Szczepanski – USA Today Sports

So where has David strayed? Why is this happening now? Like Putz, Hernandez has altered his repertoire. He’s throwing his two-seamer 30% more often than last season. This has largely come at the expense of his four-seam fastball, which he’s using 40% less than in 2012. What’s behind this shift is unclear, but it’s not working as his two-seamer is getting hit hard and has been costing him dearly. David’s curveball, his best offering last year, has also been far less effective in 2013. On the bright side, his changeup has improved but without fastball success, the changeup’s usefulness is limited. Like JJ, batters are taking more and chasing less since Hernandez is struggling and hitters know it. They are taking advantage of the situation by forcing David to throw strikes and jumping on hittable pitches.

I wanted to be able to blame the poor results of the back-end of the bullpen on bad luck. Unfortunately, the BABIP of both JJ and David are right in line with their career averages, showing that we can’t just hope for regression to the mean. Instead, there is some puzzling information within just how they are pitching. Will JJ’s velocity pick back up? Can he command the splitter and get it back on track as one of the game’s premier put-away pitches? Will David either get his two-seam fastball under control or start using it less? What about his curve? Can both of these guys find a way to keep the ball in the yard?

The Dbacks season rests in their hands and given the competitive nature of the division, there are sure to be a ton of close games as the season wears on.  Can they rise to the occasion and iron out their issues? We certainly hope so.