Looking at stat projections for the Nats lineup

The 2018 Nationals are going to look a lot like the 2017 Nationals. With only a handful of exceptions, the same group of players that won 97 games last season is going to be back and making another run at it this season.

So while many other clubs' fortunes will be predicated in large part on how much they improved their roster during the offseason, the Nats' fortunes probably boil down more to this question: How much better (or worse) will their returning players be?

We won't know the answer, of course, for another nine months. But that doesn't mean we can't start looking at the possibilities right now. FanGraphs certainly is.

The analytics-heavy baseball site already has published its Steamer projections for the 2018 season. That system uses past performance and aging trends to make future projections on players, and though obviously a whole lot of unpredictable factors will impact a player's actual production, it's still fun to look at these things and wonder how close to accurate they'll be.

So let's look at some of the Nationals' most important players, their actual stats from 2017 and Steamer's 2018 projections for them. We'll start today with position players, then return tomorrow with pitchers ...

BRYCE HARPER
Actual 2017 stats: 492 PA, 29 HR, .319 AVG, .413 OBP, .595 SLG, 4.8 WAR
Steamer 2018 projection: 622 PA, 37 HR, .303 AVG, .420 OBP, .585 SLG, 6.1 WAR
Comment: This seems like a fairly safe bet for Harper, with numbers comparable to his MVP-caliber numbers from last season, with one major change: 130 more plate appearances, which he lost in 2017 after suffering his mid-August knee injury.

ANTHONY RENDON
Actual 2017 stats: 605 PA, 25 HR, .301 AVG, .403 OBP, .533 SLG, 6.9 WAR
Steamer 2018 projection: 630 PA, 23 HR, .283 AVG, .376 OBP, .481 SLG, 4.8 WAR
Comment: The projection sees Rendon cooling off from his outstanding 2017 performance. Maybe that's reasonable, if you consider everything went right for the third baseman last year. But I don't think anyone would be surprised if he duplicates his numbers, would you?

DANIEL MURPHY
Actual 2017 stats: 593 PA, 23 HR, .322 AVG, .384 OBP, .543 SLG, 4.3 WAR
Steamer 2018 projection: 573 PA, 18 HR, .311 AVG, .368 OBP, .499 SLG, 2.9 WAR
Comment: The fear with Murphy is that at 33, coming off major knee surgery, it's too much to expect the same kind of production he provided in 2016 and 2017. That's fair. Murphy (and other supporters) would probably suggest looking at Justin Turner's 2016 performance with the Dodgers after undergoing the same microfracture surgery as counter-evidence that a dropoff is hardly a given.

TREA TURNER
Actual 2017 stats: 447 PA, 11 HR, .284 AVG, .338 OBP, .451 SLG, 3.0 WAR
Steamer 2018 projection: 563 PA, 15 HR, .298 AVG, .347 OBP, .466 SLG, 3.6 WAR
Comment: Out of everyone in the Nationals' regular lineup, it's most reasonable to expect improvement from Turner. He had a sluggish start to his 2017 season, then just when he got hot, he was struck by a pitch on his wrist and missed two months. If he can stay healthy, there's plenty of reason to believe he's going to have a big year.

RYAN ZIMMERMAN
Actual 2017 stats: 576 PA, 36 HR, .303 AVG, .358 OBP, .573 SLG, 3.3 WAR
Steamer 2018 projection: 544 PA, 27 HR, .270 AVG, .331 OBP, .494 SLG, 1.1 WAR
Comment: Out of everyone in the Nationals' regular lineup, it's most reasonable to expect a decline from Zimmerman. That's not an insult to the veteran first baseman; it's simply recognition of how good he was last year, and how unexpected that was. Could he do it again? Sure. There have been plenty of 33-year-olds who have put together seasons like that. But nobody should just assume it's going to happen. Truth be told, if the Nationals can get 544 plate appearances and an .825 OPS out of Zimmerman in 2018, they probably wouldn't be complaining too much.

MICHAEL A. TAYLOR
Actual 2017 stats: 432 PA, 19 HR, .271 AVG, .320 OBP, .486 SLG, 3.1 WAR
Steamer 2018 projection: 499 PA, 17 HR, .245 AVG, .305 OBP, .417 SLG, 1.1 WAR
Comment: Let's just say the computer formula isn't buying Taylor's breakthrough performance last season. Given his production the previous two seasons, that's understandable. If you've watched him throughout his career to date, though, you have to admit you saw a significant difference in 2017. Maybe there was some luck involved, but Taylor (like Wilson Ramos the previous year) showed vastly improved plate discipline and the ability to drive pitches on the outside corner to right-center field. Maybe he'll go through more prolonged slumps this season, but the guess here is what we saw last season wasn't a complete fluke.

MATT WIETERS
Actual 2017 stats: 465 PA, 10 HR, .225 AVG, .288 OBP, .344 SLG, -0.2 WAR
Steamer 2018 projection: 418 PA, 13 HR, .246 AVG, .308 OBP, .400 SLG, 1.3 WAR
Comment: The Nationals are counting on a bounceback season from Wieters, and the computer seems to think he has one in him. While those projected stats aren't going to merit an All-Star selection, they are improved from 2017 and suggest Wieters isn't totally done as an everyday catcher. The Nats do intend to give him fewer at-bats this time around, and the projection suggests the same thing. If this one comes true - and if Pedro Severino, or whomever ends up as the No. 2 catcher, can be productive - the Nationals should see some real improvement here.

ADAM EATON
Actual 2017 stats: 107 PA, 2 HR, .297 AVG, .393 OBP, .462 SLG, 0.5 WAR
Steamer 2018 projection: 623 PA, 12 HR, .282 AVG, .358 OBP, .416 SLG, 2.0 WAR
Comment: We'll never know what Eaton might have done over a full season in 2017, his campaign abruptly cut short by a torn ACL after only four weeks. He was awfully good during those four weeks, though. Maybe he won't be the same player anymore as a result of his reconstructed knee. But players do come back from torn ACLs and recapture their pre-injured form. If he does, Eaton should exceed these projections and be more than a 2 WAR player.