Trea Turner could change the Nationals’ season. (Nick Wass/Associated Press)

Slowly but surely, the Washington Nationals have filled the holes on their not-so-porous roster. They got the big bench bat they needed, Matt Adams. They re-signed the proven late-inning reliever they wanted, Brandon Kintzler. With their Opening Day starting eight relatively set and four-fifths of their rotation returning, they need not do much more than that to begin next season as heavy favorites in the National League East.

But while they have no dire need for a position-playing star, or much room to add one, the Nationals could still find themselves with a weapon in their 2018 lineup they did not often have this past year — a fully healthy Trea Turner.

Turner started last season slowly, then succumbed to an April hamstring injury, then finally worked his way back into havoc-wreaking form by a late-June series against the Cubs. Reliever Pedro Strop hit him on the wrist with a pitch in that series, and he missed two months. He played 98 games, wrestling for rhythm as he worked his way back from two injuries, and hit .284 with a .789 on-base-plus slugging percentage despite the interruptions. He did not look like the rookie of the year finalist who broke out in 73 games in 2016. But he showed flashes of the future MVP candidate many baseball followers — enamored by his speed and acumen — think he could be.

“Nothing that was bothering me last year is bothering me now. I feel really good, really refreshed,” Turner said at Nationals Winterfest this monht. “It’s just a matter of staying healthy for 160 games. The wrist, I couldn’t really control. But you want to be out there as much as you can.”

Turner has still never played a full major league season at shortstop. He played 73 games in 2016, mostly as a makeshift center fielder. He played 95 games at shortstop in 2017, battling injuries through his first year as the full-time starter. He did not play enough games to qualify for most statistical leader boards, but if he had, Turner would have finished 18th in Ultimate Zone Rating per 150 games (UZR/150) among major league shortstops with 2.2. For reference, among those who played at least 400 innings at shortstop last season, Wilmer Difo (9.9) ranked third in the majors in the defensive statistic behind only Andrelton Simmons and Jose Iglesias.

Turner demonstrated ample arm strength in his healthy days at shortstop, thereby stiff-arming the only critique most evaluators had against him at the position. He adopted a habit of jumping into throws that most shortstops complete while grounded — much to the chagrin of some infield coaches within the organization — but the major league staff never felt much need to push him to a more fundamental approach. Turner was comfortable with the move, which allowed him to throw in tight time without thinking, and used it successfully. And he was happy with his defense overall.

“I felt like I was more consistent. Some of the errors I made were very easily fixed,” Turner said. “I felt like I made more diving plays, just because I was slowing things down and I felt like I had more time on a diving play than I thought. Previous years, I was learning my body and how to position yourself to make plays.”

Turner will get another shot at shortstop this season, and with it a chance to add yet another all-star-caliber offensive force to the Nationals’ lineup. Turner finished the season with a WAR (Wins Above Replacement) rating of 3.0, which set him in the middle of the major league shortstop pack. Given that number, Turner projected to accumulate 4.9 Wins Above Replacement over 160 games. Only four major league shortstops accumulated at least that many — Francisco Lindor, Corey Seager, Zack Cozart and Simmons.

New Nationals Manager Dave Martinez has already said he anticipates Turner hitting second behind Adam Eaton, giving the Nationals a speedy and potent top of the order ahead of one of the most potent middles of the order in baseball. But Turner has always stated an affinity for the leadoff spot, where he can run freely. He doesn’t have the high walk rate preferred in leadoff men these days, and indeed, one of the main knocks against his offensive game remains his inability to draw walks and see pitches. But he will be asked to fill more of a calculating, controlled offensive role in hitting behind Eaton, one in which his duties include moving runners and hitting to situations. Turner batted second in the minor leagues and has batted third in amateur situations, too. But he has hit first in 157 major league games and second in 14. He will need to adjust.

“I don’t lead off the way people normally lead off [either]. For me, it’s about being the best hitter you can possibly be,” Turner said. “I don’t think that always entails slapping the ball the other way, bunting. But in the two-hole, you get more of those opportunities, and you need to be able to do that . . . it also depends who’s on first. If you have a faster guy that’s stealing bases, then you’ve got to take pitches. If you’ve got a guy that’s not stealing bases, then I don’t know if it necessarily matters. I just try to be the best hitter I can possibly be. And I think that plays in all spots.”

Exactly what the best version of Trea Turner is remains to be seen. His 2017 season qualified as a regression from his remarkable second half in 2016. At this point in his development, the 24-year-old is likely something between the two. He is a .304 career hitter with a .840 career OPS. “In between the two” still places him among baseball’s best.

And because of the hamstring trouble he experienced last season, and the lack of offensive rhythm he fought through all the way, Turner only had about half a season of freedom on the bases. He still finished third in the majors with 46 stolen bases and projected to steal 75 over a full, healthy season. No one in the majors stole that many. Few have the game-changing tools that Turner does. If he can stay healthy in 2018, few teams will have the variety of offensive weapons the Nationals will — and they will not even have to make a move to accumulate that arsenal.

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