Ronald Acuna Jr. beat out Nationals outfielder Juan Soto for the National League rookie of the year award. (Kiyoshi Ota/Getty Images)

Juan Soto’s rookie year was spotted by few hiccups, few missteps and few individual defeats even as the Washington Nationals sputtered in the standings and finished eight games out of the playoffs.

But Soto did take a slight loss Monday evening, finishing second to Atlanta Braves outfielder Ronald Acuna Jr. in the National League rookie of the year race, the Baseball Writers Association of America deciding that Acuna had a slightly more impressive season than did the Nationals' young star. Acuna won the award by a wide margin, earning 27 of the 30 first-place votes, while Soto received just two to finish in second place. Los Angeles Dodgers starting pitcher Walker Buehler finished third.

In the American League rookie of the year race, Japanese slugger-pitcher Shohei Ohtani of the Los Angeles Angels topped the New York Yankees' Gleyber Torres and Miguel Andujar.

“You really can’t go wrong with either Juan or Acuna, both will be great players in our league and our division for a long time,” Nationals Manager Dave Martinez said in late September when asked about Soto and Acuna as rookie of the year candidates. “Of course, I think the rookie of the year is Juan Soto. He has done things no other teenagers have. He has been incredible, but it could go either way and baseball is lucky to have both those guys."

Juan Soto, seen on his current MLB tour of Japan, came up short for NL rookie of the year. (Kiyoshi Ota/Getty Images)

Soto, who turned 20 in October, built his case on all that he accomplished at 19 years old. He bested Hall of Famer Mel Ott for most walks by a teenager since 1900. He finished with the second-most home runs by a teenager in history, tied with Bryce Harper and better than Ken Griffey Jr., Mickey Mantle and many others who became either Hall of Famers or superstars. But he was ultimately outpaced by the 20-year-old Acuna, who thrived once the Braves moved him into the leadoff spot in the middle of the season.

Acuna’s and Soto’s numbers were near-identical, and it was long established that Buehler, despite his 2.62 ERA and shutdown second half, was on the outside of a two-horse race that ultimately tilted heavily in Acuna’s favor. Acuna made his major league debut a month before Soto was called up in mid-May, but Soto ended up playing in 116 games while Acuna appeared in 111. Acuna ended up with a slim advantage in home runs (26 to 22), runs scored (78 to 77), hits (127 to 121) and batting average (.293 to .292). Soto, on the other hand, had more RBI (70 to 64), an edge in on-base-plus-slugging percentage (.932 to .917), walked considerably more (79 to Acuna’s 45) and struck out less (99 to Acuna’s 123). That all helped Soto compile a .406 on-base percentage to Acuna’s .366, and the numbers are comparable considering that Soto had just seven more plate appearances on the season.

But Acuna was set apart, most likely by his defense, base running and role in pushing the upstart Braves into the postseason. While rookie of the year is an individual award, a close race can take team success into account. Acuna also showed more promise as a left fielder, a spot Soto was still getting accustomed to in 2018, making him a better all-around option given how similarly the two players fared at the plate.

In the AL, Ohtani won the award following a debut season that failed to live up to the massive hype surrounding the Japanese star, a rare full-time two-way player, and yet still delivered a historic performance. Ohtani received 25 of the 30 first-place votes, while Andujar finished with the other five.

Ohtani, 24, was billed as the Babe Ruth of Japan in his native country, and he became the first MLB player since Ruth in 1919 to amass 20 home runs and 50 innings pitched in the same season. He finished with a .285 batting average, .361 on-base percentage and .564 slugging percentage with 22 home runs in 326 at-bats and he went 4-2 with a 3.31 ERA and 63 strikeouts in 51⅔ innings. His .925 OPS would have ranked sixth among AL hitters and his ERA eighth among starting pitchers if he had enough at-bats and/or innings to qualify.

But Ohtani’s season was hampered by injuries, most notably a torn elbow ligament that limited him to just one trip to the mound over the season’s final three months. He underwent Tommy John surgery in October and will be limited to being a full-time designated hitter in 2019, with a return to the mounded slated for 2020.

“Putting numbers aside — I don’t even want to talk about numbers — I was just kind of disappointed I wasn’t able to play a full season,” Ohtani said through an interpreter Monday night. “I feel like elite players should be able to play a full year and help out their team.”

Andujar, meanwhile, turned an April stint as Brandon Drury’s replacement at third base into a permanent job with the Yankees. He batted to a slash line of .297/.328/.527 with 27 homers in 573 at-bats and led all MLB rookies in hits (170), doubles (47), RBI (92) and extra-base hits (76). He was seeking to become the Yankees’ second straight winner of the AL award, after Aaron Judge won unanimously in 2017.

And yet it was Ohtani’s debut season, though only consisting of a limited number of at-bats and 10 starts, that earned a spot alongside Acuna as this year’s best of the league’s youngest stars.

Dave Sheinin contributed to this report.

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