By: Will Burchfield

J.D. Martinez lives to play baseball — specifically, he lives to hit baseballs.

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The former Tigers slugger is so scrupulous about his approach at the plate he keeps a detailed log of every pitcher he’s ever faced. It’s contained in a little notebook that Martinez updates after each at-bat. The notebook goes where he goes. In July this season, when the Red Sox come to town, it will wind up in the visitor’s clubhouse at Comerica Park. Then, by way of its owner’s backpocket, it will travel to the dugout.

Tigers manager Ron Gardenhire gained an appreciation for Martinez’s thirst for the game when he coached him in Arizona for three months at the end of last season. During his time with the Diamondbacks, Martinez morphed into the best hitter on the planet. Soon thereafter his agent bestowed on him a nickname: “King Kong of Slug.”

The Tigers will miss this beast in their lineup this season. If there’s a player who can step into Martinez’s shoes, it’s likely the same one who’s taking his place in right field: Nicholas Castellanos. The soon-to-be 26-year-old, coming off a career year, figures to be the most potent run producer on the team.

“He reminds me so much of J.D.” Gardenhire told reporters on Thursday, via the Detroit News, after Castellanos hit his second home run of the spring. “Being around him, the intensity, I am telling you, it’s the same. Those two, I don’t know if they hung around together or what, but it’s the same — the same drive, and it’s pretty cool.”

Martinez sat about two lockers down from Castellanos in the Tigers clubhouse last season. The veteran’s laser-like focus may have rubbed off on his younger teammate. Castellanos is a distant person by nature, much more so than Martinez, prone to putting up walls and drawing within himself. This aloofness was especially pronounced last year, but maybe it was his way of blocking out the noise.

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If so, it seemed to work.

Castellanos’ numbers weren’t always pretty, but he smacked the ball from almost start to finish. Only four players in baseball — Joey Gallo, Aaron Judge, Paul Goldschmidt and Corey Seager — managed a higher rate of hard contact. Castellanos was let down by some woefully poor luck, but still finished with a team-leading 26 home runs and 101 RBI and an MLB-leading 10 triples. His 72 extra-base hits ranked 11th overall.

His fortune finally turned in September when he hit .368 with seven home runs, 25 RBI and a King Kong-like .649 slugging percentage. That’s where he’s picked up in spring training. Castellanos has four hits in 10 at-bats, including two home runs and a triple.

“I am just continuing how I finished last year. I’m not trying to think about it. Just taking good swings at good pitches,” he said.

That’s the kind of simple explanation for which Castellanos is known. He’s trying to answer a far more difficult question on defense: Can he successfully transition from third base to right field? The early returns last season were ominous, but Castellanos seems to be getting more comfortable this spring.

“To be honest with you, I feel comfortable in all aspects of the game right now. Obviously, I am not saying I’ve peaked or I can’t get better. Just in the sense that, I love playing outfield and love hitting,” he said. “I’m kind of in a good spot right now.”

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Martinez, by the way, was never a good defensive player himself. But he made up for that in a big way at the plate. His replacement has a chance to do the same, and Castellanos is already looking the part.