Opposing hitters had a .271 AVG against Trevor Rosenthal’s fastball in 2017. He averaged 98.4 MPH with the heater, which got up to 101.5. He threw his slider more than he’d ever thrown it before (12.9% of the time, up from 5.8% and 6.8% in the previous two seasons), holding opposing hitters to a .097 AVG on the pitch, and the former St. Louis Cardinals’ closer mixed in a changeup (12.5%, down from 17.2% and 13.9% the previous two seasons), with hitters putting up a .135 AVG on the offspeed pitch.
Rosenthal made 50 appearances total in 2017, putting up a 3.40 ERA and a 2.17 FIP, 20 walks (3.78 BB/9), 76 Ks (14.35 K/9), and a .206/.294/.278 line in 47 2⁄3 innings before a torn UCL in his right elbow ended his campaign and forced him to undergo Tommy John surgery which cost him the entirety of the 2018 season.
In a conference call with reporters on Monday afternoon, after Rosenthal passed a physical and signed a 1-year/$6M deal with the Nationals, the veteran right-hander said he wouldn’t switch much up in terms of pitch selection now that he’s recovered from Tommy John and ready to get back to work on the mound in 2019, though he did take advantage of the time off to start looking into advanced metrics he thinks could help him now that he’s 100% and set to return.
“I think I’m going to pretty much be the same as far as my repertoire,” Rosenthal said.
“Mechanically, I’ve just been working on a few things that I’ve learned just biomechanically and how to just use my body’s energy more efficiently, and then obviously just with improved strength and conditioning and all that that I took advantage of over this time off, I think will just help me over the [long term], and just using some different technology and working on the spin of my breaking ball, just trying to enhance my breaking ball. My fastball is kind of going to be what it is, and then my changeup is going to be there as a primary weapon as well.”
“I think everything is going to be similar to what we’ve seen in the past,” Rosenthal added, “but hopefully just a little bit extra time and work always trying to improve and make everything a little bit better.”
Rosenthal gradually decreased the use of his curveball (against which opposing hitters had a .314 AVG between 2012-16) before abandoning it completely in 2017, and he said Monday that he’d likely stick with the three-pitch mix he was working with before the injury when he takes the mound for the Nationals in 2019.
“That’s kind of my plan right now,” Rosenthal explained, “and that’s what I was working on — I wasn’t able, obviously, to work on it a bunch early in the process, because I was just throwing and just playing catch and getting the volume up on my throwing, but towards the end I started using some different technology and looking at the spin axis and all these different things that I didn’t have a lot of information on before, so I’m hoping over those few weeks that I did that and then the weeks to come leading into Spring Training I can dial in on that a little bit more, hopefully understand it, and make some adjustments and definitely get more of a true breaking ball — something — whether it’s a slider, a cutter, or curveball, something that I fully understand what it’s doing and am able to repeat it consistently.”
Will he be able to take the mound consistently in 2019, or will he be on an innings limit in his first season back from TJS?
“That’s something that I haven’t talked about,” Rosenthal said on Monday.
“I think in my mind I don’t see going into the season that there’s going to be a really hard stop or an exact limitation to what I’m going to do. In general terms, there’s just some innings and games and not [exceed] the threshold of what the normal workload would be, but again, what I’ve received from the medical staff it seems like they do a really good job of prioritizing and monitoring the usage and just the recovery and everything that’s involved in that process, so I mean, I’m sure it’s something that I’m going to lean on them heavily for their feedback, but going into it I don’t think there’s going to be a solid stop, at least from my perspective as we head into the season.”
While he was in D.C. to sign the deal with the Nationals, the right-hander said he didn’t really discuss what his role will be in the bullpen.
He closed out games for the Cardinals in the past, earning 93 saves between 2014-2015, but he saved just 25 total in 2016-17.
Rosenthal said he’s going to pitch in high-leverage innings, but he doesn’t care if it’s in the eighth or ninth, especially the way the trend in the majors has gone recently with big arms throughout the back end of the bullpen.
“I think — it’s not something that I necessarily think about — I haven’t thought about it throughout this process,” Rosenthal said of his role with the Nationals, “... but yeah, just seeing what teams are doing, even with the Nationals bringing me in ... having an established closer with [Sean] Doolittle and bringing in another guy like me with similar attributes, I think the teams are validating that now and it’s something that’s proved to be a strength, especially when you have starting pitching like what the Nationals have and you can build on the back end of that. I think it’s proven to be successful over the season and then especially down the stretch run.
“For me it’s definitely valued because I get the opportunity to kind of go back and forth in whatever those high-leverage situations might be throughout the season.”