Trea Turner is trying to replicate his 2016 production this season. (Jonathan Newton/The Washington Post)

WEST PALM BEACH, Fla. — Washington Nationals Manager Dave Martinez claims there “wasn’t really a book” on Trea Turner, no one strategy the Chicago Cubs, Martinez’s previous employer, utilized to attack the shortstop when they encountered the Nationals in the National League Division Series last October. The previous time the Cubs had seen Turner, he stole seven bases in three games. Martinez, then the Cubs’ bench coach, said they just wanted to avoid letting him get on base at all costs.

“When he gets on base,” Martinez said, “he causes all kinds of issues.”

The Cubs didn’t have to worry much about Turner’s base running in the five-game series. Turner went 3 for 21 with two walks and seven strikeouts. He went hitless in the first three games and stole his only base in Game 5. The Nationals’ sparkplug was neutralized for the second consecutive postseason, a frustrating conclusion to a frustrating sophomore campaign that began with a pothole. Heading into 2018, Turner is aiming to recapture his rookie form.

When Turner was promoted to the big league stage for good in 2016, expectations typical of a top prospect arrived with him. He was, after all, the Nationals’ shortstop of the future, a top-of-the-order bat with elite speed to put at the top of the batting order. But it was difficult to foresee him instantly becoming one of the best players in the National League and finishing second in the NL rookie of the year race after not playing every day until the end of July. Even for him.

“I don’t think me or anybody expected ’16 to go as well as it did,” Turner said. “So to me, I think, it was just like, ‘“Wow, I can do more than I think I can.’”

Which perhaps made his production in 2017 more frustrating than for the typical 23-year-old shortstop in his first full major league season. Making the switch back to shortstop after finishing 2016 in center field, Turner was on the 10-day disabled list with a strained hamstring less than a week into the season. It took until a week in late June for Turner to finally break out over a sustained stretch. He went 5 for 5 one day against the Cincinnati Reds. He stole eight bases and walked more than he struck out over the seven games — a small sample size but encouraging nonetheless.

Then, on June 30, after terrorizing the Cubs for four days, Turner was plunked on the right wrist by a 96-mph fastball by Pedro Strop in the ninth inning of the series finale. The wrist fractured. Turner wasn’t back in Washington’s lineup for two months. After batting .342 with a .937 on-base-plus-slugging percentage in 324 plate appearances in 2016, Turner batted .284 with a .789 OPS in 447 plate appearances in 2017.

Around the absences — and perhaps because of them — Turner said he developed bad mechanical habits in the batter’s box. He found himself in a different hitting position than in 2016. Replicating that season’s production, as a result, was unlikely. He has worked this spring with hitting coach Kevin Long to restore his 2016 form.

Long, a leading launch-angle enthusiast, is convinced Turner is a line-drive hitter because his swing is “very on plane” with the baseball. The problem last season, therefore, wasn’t his swing. Long thinks it was his approach. The man credited with shepherding Daniel Murphy’s midcareer transformation wants Turner to hit the ball on the ground more to the right side while lifting the ball to his pull side.

“That’s what I did [in 2016],” the 24-year-old Turner said. “When they threw me away, I took my hit, the single or maybe in the gap for extra bases. But then when they pounded me in, I could hit it out of the park that way. I’m not necessarily going to just flick the ball to right field and hit a homer. I really have to drive it, which I can do, but I have to take a great swing on a good pitch. For me, if I can take my hits that way, it’s fine with me.”

The difference was notable. Turner’s line-drive rate dropped from 25.5 to 14.8 percent, his groundball rate jumped from 43.1 to 51.7 percent, and his hard-hit ball rate sank from 34.8 to 26.7 percent. The result? A nose-dive in BABIP, batting average on balls in play, from a staggering .388 to .329. Luck is a factor in BABIP, but the differences in batted balls impacted Turner’s production.

Furthermore, Turner said teams pitched him differently last year than in 2016. Two years ago, Turner said, opponents fed him a steady diet of fastballs because they didn’t want to give him a free base. Last season, he encountered a more diverse pitch selection. Turner explained the difference is laying off pitches to put himself in favorable counts more often.

“When you prove you can hit, you get tough pitches to hit,” Turner said. “And then you got to prove you can take them. And when you prove you can take them, they’ll give you pitches to hit. It’s back and forth, back and forth.”

Turner began last season in the No. 2 spot in the order but jumped to the leadoff spot when Adam Eaton tore his anterior cruciate ligament in late April. As a leadoff batter over the past two years, Turner often hit ahead of the departed Jayson Werth, one of the most patient hitters in baseball. Werth’s tendency to work deep into counts afforded Turner rampant opportunities to steal bases.

This season, Turner will bat second again with Eaton’s anticipated return, usually hitting in front of Bryce Harper. Turner said they have already had conversations about possible situations they could encounter.

“I’ve always told everybody that hits behind me, swing at whatever you want because if you hit the ball in the gap, I’ll score,” Turner said. “I don’t care that much about stolen bases. So when I steal and a guy fouls a pitch off, for me it’s not that frustrating. I’ve always tried to make that a priority to the guys behind me. At the same time, I’m still going to try to be aggressive, but I have to know when to be aggressive on what guys do and don’t like.”

Martinez insisted Turner will have the green light on the base paths again. The manager wants his club to run the bases aggressively, and that starts with one of the fastest players in baseball. Turner needed just 98 games to swipe 46 bags on 54 chances after compiling 33 steals in 73 games in 2016. He smirked when asked how many bases he could have stolen if he avoided the disabled list.

“I don’t know,” he said. “Twenty more maybe? I don’t know. I just want to be healthy this year.”

As his manager knows: When he gets on base, he’s a problem.

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Max Scherzer doesn’t think he’s reached his peak: ‘I may be better in 2018’

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Watch: Nats fans audition to sing ‘Star-Spangled Banner’

‘It’s not fair to my teammates or myself’: Bryce Harper explains why he won’t talk about 2019