Prospect Notebook: Zack Von Rosenberg Switches to a Two-Seam Fastball
When Zack Von Rosenberg was drafted, the Pittsburgh Pirates didn’t have any ace pitching prospects. Jameson Taillon was a year away from being drafted. Luis Heredia was a year and a few months away from being signed. Gerrit Cole was two years away from being drafted. And the last time the Pirates had an ace in the majors was arguably when Doug Drabek was on the team.
The hope with the 2009 draft class was that one of those pitchers could emerge as a top of the rotation guy. Guys like Taillon and Cole had top of the rotation upside when they were drafted. With Von Rosenberg and company, the hope was that one of them could add velocity, or just have the overall combination of stuff and the ability to pitch which would lead to them being an ace. Since Von Rosenberg had the biggest bonus ($1.2 M) and was the highest rated prospect (#41 overall by Baseball America before the draft), he was seen as the guy with the best shot.
The story of Von Rosenberg’s career has had two main topics: his fastball never added velocity and he left that fastball up too much, getting hit hard in the process.
Von Rosenberg had, and still has, a tall and skinny frame. The hope was that he would add velocity as he added muscle and filled out that frame. That didn’t happen, and he was throwing in the 88-91 MPH range. He was also leaving that 88-91 MPH fastball up in the zone, which led to a lot of trouble. Von Rosenberg stayed behind in extended Spring Training last year, trying to work on that issue. This year he showed signs of giving up on the pitch — at least on the hope of driving it down in the zone. He added a two-seam fastball, or more accurately brought it back. Von Rosenberg had thrown the pitch in high school, but the Pirates take the two-seamer away from young pitchers and have them focus more on the four-seam until they reach high-A or Double-A. The purpose of the pitch is to keep the ball low in the zone and get ground balls, which is something his four-seam wasn’t doing.
“A fastball up in the zone in my three years in the minor leagues, full season-wise, it’s gotten hit,” Von Rosenberg said. “So keeping it down is my big thing. It’s what I have to live by, or I’m going to get crushed.”
The two-seamer has a lot of late sink, and has shown some improvements throughout the early part of the season. He started throwing the pitch more in Spring Training, and has been focused on his arm action and command of the pitch. The arm action makes his delivery look different, as he is trying to be long and loose with his arm, leading to a delivery where his arm is extended further above his head.
“I’m pretty comfortable with throwing it too, because you have the conviction to know that even if I don’t throw it where I want to throw it, that the run and the sink on the baseball, they can still swing and miss or hit a ground ball,” he said. “So it’s a lot easier to throw a pitch that you know you can screw up and still be effective with it.”
Early in camp he was only throwing the pitch in the 80-83 MPH range. He slowly added some velocity and went up to 85 by the end of camp. He noted at the end of camp that he can throw the pitch in the upper-80s, which is a good area for a two-seam fastball with sinking action. He’s been doing long-toss, building up arm strength by going out to 270 feet. He hopes to eventually move out to 300 feet. So far the approach seems to be working. Von Rosenberg has been in the upper 80s this season, working in the 87-89 MPH range two appearances ago.
He still throws the four-seam fastball, but he’s mostly throwing off the two-seam.
“If I want to throw a miss pitch, I’ll throw a four seamer,” Von Rosenberg said. “If it’s going to be off the plate, or high, change your eye level. Because you don’t want to throw a high two seamer. It might sink down into the zone and they might hit it pretty hard.”
Like a lot of the Bradenton pitchers, Von Rosenberg has been the victim of poor defense. He gave up three unearned runs in his second outing. His third outing he gave up an earned run thanks to a hit which should have been an error. He’s also been hit around some. In his last appearance he gave up three runs on five hits in three innings, with a few hard hit balls.
He doesn’t have a big chance to be that top of the rotation starter one day. That’s not a bold statement, since he’s currently pitching long-relief out of the high-A bullpen, stuck behind Eliecer Navarro and Matt Benedict, who aren’t top prospects. At this point he’s more about deception and pitching than hoping for an increase in stuff.
“I’m not that guy,” Von Rosenberg said. “I’ve gotta be a little deceptive. I’ve got to, not necessarily fool guys, but make them uncomfortable enough to not know what’s coming next and be unsure of themselves and create doubt in their head. That’s my plan.”
So far the two-seamer has been a little inconsistent. Von Rosenberg isn’t dominating with the pitch yet, but it’s showing more potential than his four-seamer did. The results still aren’t there, and struggling out of the bullpen is not a good sign for his future. But it’s early and he’s only been really focused on the pitch for a few months. The hope is that it gets more consistent, and becomes a pitch he can use to get ahead in the count or get quick outs with. He’s going to need a fastball to set up his off-speed pitches. He’ll also probably only be a finesse starter at this point, which is a much lower upside than people were hoping for in 2009. He’s got a great curveball and changeup, but those are pretty useless without a good fastball.
“If they’re not there, then I’m in trouble,” Von Rosenberg said of his off-speed stuff. “I don’t see myself being a 95 MPH guy. I see myself as a guy that’s got to, not necessarily nibble, but attack the zone, down in the zone, and be able to throw all of my pitches for strikes at any given time. Have that and get in hitter’s heads. There’s a lot of those guys in the big leagues. I know my role, and I just have to own it and just become that guy.”
The Theory Behind Long Tossing
Long tossing is a topic I’ve discussed on this site many times. The term long tossing includes throwing from 120 feet, but people generally associate it with going well beyond that standard distance. There has been a lot written in the national media about how the Pirates don’t allow long tossing, yet I’ve given examples and videos showing that’s not true.
I don’t really keep records of how far out people go. I know that Gerrit Cole, Jameson Taillon, and of course Tim Alderson are guys who will go well beyond 120 feet. There are plenty of others who have individual throwing programs, rather than staying at 120. So when I learned that Von Rosenberg was one of those pitchers, I asked him a bit more on the subject. Von Rosenberg explained to me the theory behind long tossing, and how it can help your arm and velocity.
“The long toss is more of a flush for your arm,” Von Rosenberg said. “Once you start coming in [to shorter distances] you get that hand speed. The long toss keeps you long. So if you’re going to be short with your arm, you’re not going to be able to throw the ball very far. And once you come in, it’s where you get the hand speed to pull on the baseball as quickly as possible. That’s really the theory behind it.”
He was long tossing in high school, although his throwing mechanics weren’t as sound at the time. He stopped for a while, and is just getting back to it.
“It’s actually helping my arm,” he said. “I’m feeling better, recovering quicker too.”
Error Watch and Alen Hanson on the Bench
The errors have continued for the Marauders in the last week. I wrote about the defensive problems at the end of last week. Through eight games, they had 22 errors. They added five more in the next four games, with Alen Hanson committing three in one game.
Since that game, Hanson has been on the bench. He’s been on the bench for three games, but I don’t think it’s injury related. A lot of his defensive issues seem to be in his head, and he’s also struggling at the plate. The Marauders return home tomorrow, and I’ll be confirming the situation with Hanson when I get to McKechnie. It’s not the worst move to bench him at this point. He has ten errors, and a lot of those came from routine plays that should have been made. He could have easily had a lot more errors. I’ve heard that almost everything was ruled a hit early in the season in Port Charlotte, and he’s had several errors that were ruled hits at McKechnie.
Hanson has the skills on the field to be better than this. He also has the skills at the plate to be better than his stat line. It just seems that he needs to take a break, and hopefully this break will get him back on track.