The Nats obviously need starting pitching help this off-season. Max Scherzer is and will remain the staff Ace, and perhaps Stephen Strasburg will somehow stay healthy and put together a full season worthy of a #2. Tanner Roark may return or may be traded or non-tendered; should he stay, hopefully he finds the magic of his 2014 and 2016 seasons. Unfortunately, this is likely wishful thinking (as I noted in this comment).
In any case, the Nats need to fill at least two more rotation slots, and the in-house candidates have thus far been underwhelming. Recent news stories mention the Nats being potential suitors for big-name free agents Dallas Keuchel and Patrick Corbin, as well as other possibilities (FAs Nathan Eovaldi, J.A. Happ, Charlie Morton, trade candidates, etc.).
Just for fun, the following table lists stats for several pitchers.
|Nathan Eovaldi, Career||29||R||4.16||3.82||1.35||6.78||2.47|
|Nathan Eovaldi, 2018||29||R||3.81||3.60||1.13||8.19||5.05|
|Tanner Roark, Career||32||R||3.59||3.91||1.21||7.05||2.78|
|Tanner Roark, 2018||32||R||4.34||4.27||1.28||7.29||2.92|
|Gio Gonzalez, Career||33||L||3.69||3.63||1.32||8.67||2.30|
|Gio Gonzalez, 2018||33||L||4.21||4.16||1.44||7.79||1.85|
|Charlie Morton, Career||35||R||4.23||3.95||1.37||7.41||2.20|
|Charlie Morton, 2018||35||R||3.13||3.59||1.16||10.83||3.14|
|J.A. Happ, Career||36||L||3.90||4.10||1.31||7.98||2.44|
|J.A. Happ, 2018||36||L||3.65||3.98||1.13||9.78||3.78|
For the named players, I included both a career statline and one for 2018. It's always interesting to me when a guy has a year dramatically better than his career line; sometimes it's a sign he's found some new pitch or approach (and can thus be expected to continue), and sometimes it's just a lucky year (never to be repeated?). The same can be said for a year particularly worse than the career line; sometimes it's a sign of things to come, and others, it's just an off year.
Both Gio and Tanner had years that were not as good as their career averages. Unfortunately, in both cases, I'd expect these trends to continue. Whether it's age-related decline, velocity loss, or other factors, both have been trending downward in recent years.
Eovaldi, Morton, and Happ all had better-than-career-average years (and in the cases of Morton and Happ, they've both had multiple consecutive seasons of improved numbers). Eovaldi had the added (recency) bonus of pitching very well in the bright lights of the postseason. All three of these pitchers stand to get paid very well this offseason - projections have them in the $15M-$16M range per season.
But what about Players A through D at the top of the table, all 29 years old for the upcoming season? Player A looks very solid, with numbers comparable to Eovaldi, Morton, and Happ, albeit lower SO9 (strikeouts per 9 innings). Player D looks even better. Player B looks okay, with still good SO9 and SO/BB numbers, maybe a #5 starter candidate. Player C looks... awful. Why would I include this data point?
Spoiler alert... Players A through D are all the same guy, Sonny Gray of the New York Yankees. "Player A" is his career stat line. "Player B" is his stat line for 2018 - obviously pretty far off from his career numbers (but still at least respectable). "Player C" was his stat line for home games at Yankee Stadium in 2018, while "Player D" was his line on the road. As you'll note, he was dominant on the road in 2018, but horrific at home. Both during his career and on the road in 2018, he demonstrated the skill and tools that helped get him drafted 18th overall by the A's out of Vanderbilt in 2011. For whatever reason, he could not pitch effectively in Yankee Stadium. The Yankees have recognized this, and made no bones about the fact that they are eager to provide him a new venue.
Here's the Gray section of the table with the names and timeframes added:
|Sonny Gray, Career||29||R||3.66||3.74||1.25||7.88||2.55|
|Sonny Gray, 2018||29||R||4.90||4.17||1.50||8.49||2.16|
|Sonny Gray, 2018 Home||29||R||6.98||5.98||1.90||6.83||1.29|
|Sonny Gray, 2018 Road||29||R||3.17||2.65||1.15||9.89||3.55|
under contract for 2019 for $6.5M (EDIT: projected to earn $9.1M in arbitration) and becomes a free agent after the season. When the Yankees trade him, he will be keenly motivated to put together a solid year in preparation for free agency. With no demonstrable decline in velocity and no known injury issues this year, he seems to be a solid "change of scenery" bounceback candidate for 2019. I believe the Nats should be all in on Gray this offseason. Should he indeed return to his career norms, he's a solid #3 starter. Further, they'd be in position next offseason to either extend him or extend a QO, either getting a good pitcher (if he rebounds well enough to merit a QO) or a draft pick if he leaves for a big FA contract.
On the other hand, if he does not return to career form, he could perhaps be moved to the pen or ultimately written off. In either case, it would seem the risk involved with taking a chance on Sonny Gray this offseason is well worth the potential reward.