The Nats need to sign Jordan Zimmermann.
I don't say this lightly. I say it because if you gave me $1000 and forced me to wager it on which National would pitch the best in the majors from 2015-2019 I would have to put that money on ZNN. Strasburg is an option, but has a couple of things I don't like going on. Giolito is too far out.
Why am I so bullish on ZNN? Last year was his best year ever as a pitcher. There's gotta be a best year in every career and usually it's due to some combination of talent peaking mixing with a healthy dose of luck. But this didn't really hold true for ZNN, let's look at those stats that usually indicate luck has gone your way.
BABIP (rough range .250-.325)
ZNN : .302 in 2104, ~.290 career
This is actually the worst BABIP he has put up since his rookie year. You could argue that means he was actually unlucky last year and might get some bounce back the other way, but the take away right now is - no, not lucky with balls in play.
ZNN : 6.4%, last 4 years ~7.5-8.0%
You might want to argue that ZNN got a little lucky last year with the homers and maybe he did get a tiny bit lucky but the truth is this is the pitcher he is. He does not give up home runs.
ZNN : 75.8%, 73.3% career
Perfectly normal numbers. Nothing lucky (or unlucky here)
So if he wasn't lucky why did ZNN have a great year? Let's take a look at a couple stats that are more often indicators of improved performance from the pitcher when we look at a single season.
ZNN : 40.1%, had been ~45% the past two years.
Generally GMs and coaches like GB pitchers because GBs can't become HRs and are least likely to become XBH. If you don't walk guys then it can take three GBs getting through the infield to score a run. But the facts are that FBs are more likely to be outs than GBs so if you can keep guys in the park, FBs are actually better. ZNN can keep guys in the park. His IFFB% (basically how often he gets a pop-up) has increased the past 5 years. 5.6% to 8.8% to 9.7% to 11.0% to 14.2%.
ZNN: 8.20 and 1.31, last three years ~7 and ~1.80
Here's a big one. ZNN walked fewer batter sand struck out more than he ever had. The improvement isn't obvious looking at his K/BB rate. That was 5th best in the majors last year but it's always good (14th from 2011-2013). Instead look at his K-BB rate, which is seen a a little better indicator of skill because it pulls out some "no walk" specialists. That was 12th last year, a marked improvement from the 38th he placed at from 2011-2013.
All this is a fancy stat way of saying - ZNN didn't luck into having the best year of his career. He pitched better than he ever has.
What is it you want from a pitcher, when it gets down to it? You want a guy who stays healthy, won't walk guys, won't give up home runs, and will strike out guys. Over the past 3-4 years I count a handful of guys (8 actually) who I'd put up there with ZNN. Now factor in age and cut out those more than 2 years older than ZNN and you're down to 5. Kershaw, King Felix, Price, Sale, and Strasburg*. That's the group that ZNN is in. That's what you are let walk away.
But Harper! He's getting older! Don't you have to worry about that?
That could be an issue so let's look at a couple things that might worry you; declining fastball speed and amount of pitches thrown.
That's beautifully consistent. Tears. Losing speed is not an issue with ZNN right now.
As for pitches thrown ZNN will be up there because he has thrown a bunch of innings, but the number of pitches he averages per inning is among the lowest in the league (14.6 7th in the majors, 3rd in majors last year)
I see zero concern going into 2015.
Another thing to note is how rarely ZNN blows up. Five games with a Game Score under 30 (basically unwinnable games for your offense) since 2011. It's hard to find guys that have pitched as much as he has and not had a number of bad games.
Jordan Zimmermann was a very good pitcher from 2011-2013. He was a great pitcher in 2014. He has shown improvement in several key areas. He has no worrisome tendencies on the mound. He has no red flags due to injury or workload. He almost always gives the team a chance at winning even on his bad days. He will be 28 when 2015 starts. If you're going to sign a long term contract with any pitcher over the age of 25 it's is difficult to find a better pitcher to bet on than Jordan Zimmermann right now.
*To parse it even more there is Group A which is Kershaw and Felix who are just awesome at everything. Then there is Group B Stras, Sale who are amazing K guys who might give up a walk and a homer here and there. Price's stats bounce around the two groups not really fitting in either but may have joined the elite Group A last year, we'll see. ZNN is an amazing BB and HR guy who didn't ramp up Ks till last year.