International Free Agent Profile: OF Sung-bum Na

As was expected, the NC Dinos have agreed to have agreed to outfielder Sung-bum Na’s request and will be posting him for Major League teams to bid on. A middle-of-the-order power threat since making his professional debut in 2013, the left-hander is a career .317/.384/.542 hitter and has slugged 179 homers over the course of his eight-year career.

Sung-bum Na was born on October 03, 1989 in Gwangju, the third-largest city in South Korea. Growing up, he rooted for his hometown team, the Haitai Tigers (now the KIA Tigers), but baseball was little more than a fun game to play and watch, as he aspired to become a scientist. As he grew older, he began considering baseball as a profession more and more, as he consistently demonstrated himself to be better than his peers.

As was the case during his elementary, junior high school, and high school years, Na was a better player than virtually all of his teammates and competition while attending Yonsei University. He was fairly dominant as a pitcher, and was an excellent hitter, causing him to get an invite from the South Korean National team to participate in international events such as the 2009 Asian Baseball Championship, the 2010 World University Baseball Championship, and the 2011 Baseball World Cup, events in which Korea came in third, fourth and sixth, respectively.

In 2013, he was drafted by the NC Dinos in the second round of the 2013 KBO Draft, the 10th player overall. Though drafted as a pitcher, Dinos manager Kyung-moon Kim suggested that Na maximize the power of his potent bat by playing in the outfield every day, as opposed to pitching once a week. Na and the Dinos tested the suggestion by having Na play in the outfield in the KBO Future League and the new outfielder responded by hitting .303 and leading the league with 16 homers.

Na was called up to the Dinos in 2013. In his first full season, he hit .243/.319/.416 in 104 games, slugging 16 home runs, stealing 12 bases in 14 attempts, walking 33 times and striking out 95 times. He was named to his first All-Star game and ended up placing second in Rookie of the Year voting, behind only teammate Jae-hak Lee, who posted a 2.88 ERA in 156.0 innings pitched, allowing 123 hits, walking 59, and striking out 144. As good as Sung-bum Na was in his rookie season, he was even better in 2014. Appearing in 123 games, he hit .329/.400/.597, slugged 30 home runs, and stole 14 bases in 19 attempts while walking 42 times and striking out 128 times. In addition to being named to his second All-Star game, he won the KBO Golden Glove Award, an award given to the best overall player at every position.

Over the next few years, Na would establish himself as one of the premier outfielders in the league. From 2015 until 2018, he hit .325/.389/.538 and averaged 24 home runs per season. His best individual season during this period was 2017, when he hit .347/.415/.584, slugged 24 home runs, and stole 17 bases in 24 attempts while walking 48 times and striking out 116 times. Depending on the formulas used, his total WAR (6.6 or 4.4) was fifth or tenth among all players in the league. During this period, he won a second consecutive KBO Golden Glove Award (2015) and was elected to four more All-Star games.

In 2019, Na was limited to just 23 games after tearing his right ACL and undergoing surgery to repair it. While at second base, he attempted to advance to third base on a wild pitch. While sliding, his leg got caught on the bag and twisted at an unnatural angle thanks to his body’s forward momentum, tearing the ligament. He was stretchered off the field and taken to a local hospital in an ambulance.

Almost a year to the day, he returned to the field, as the KBO season was delayed for roughly a month thanks to the coronavirus pandemic. “My injury was really serious, so coming back on the field felt kind of weird. I was thinking about all of last year, all the hard work I had done in rehab to get to that point,” he said during an interview with ESPN. “I thought of everything that happened, but I wasn’t nervous. It was fun to be back. Opening Day was exactly one year from my knee surgery. May 5, 2019 was the day of my surgery. And I thought about that, and about how much fun it was to be finally back on the field.”

Na wasted no time, going 2-3 with a walk and a solo home run in his first game back, starting the season off like gangbusters. He showed no real rust and hit .324/.390/.596 on the season, slugging a career-high 34 home runs, walking 49 times, and striking out148 times. The lone blemish to his season came in September, when Na pulled his left hamstring while running out a single and was diagnosed with a Grade 1 strain, causing him to miss a handful of games.

Na has a relatively quiet set-up at the plate for a player from Korea, where very large leg kicks are the norm. Standing slightly crouched, he holds his hands high, wrapping his bat behind his head. Using a toe tap or small leg kick during his load as a timing mechanism, Na’s upper half and lower half often get out of sync during his swing and follow through, as his torso rotation is often late. Even still, his solid 6’0”, 220 lb. frame generates high bat speed and exit velocity numbers, about on par with the major league average, with an average launch angle of approximately ten degrees.

The left-hander swings a lot, taking hacks at almost 50% of the pitches he sees, and striking out at about a 20% rate. He’s been especially susceptible to high fastballs and pitches that fall out of the zone that he goes fishing for. He generally goes up to the plate looking for fastballs, looking to drive anything over the plate that he can get good extension on. According to Na, “Everyone has shortcomings, so I focus on maximizing my strengths. I think it’s better to reinforce other areas such as home runs, even if strikeouts increase.”

While Changwon NC Park, the home of the NC Dinos, is one of the largest parks in the KBO, listed as 331’ down the lines and 401’ to dead center, the stadium is slightly hitter friendly due to Changwon’s warm, humid summer weather, favorable winds, and relatively little foul territory. That is not to say that Na is an illusion of his environment, as his raw power is legitimate, but what may be home runs in Korea due to a more favorable hitting environment may not be in the U.S.

Defensively, Na is a solid outfielder. He possesses average-to-above-average speed and has a cannon of an arm- he has been clocked as high as 92, 93 MPH while pitching- and would fit well at any defensive position. While he may profile better in right field given his combination of tools, his combination of raw speed and an above-average arm makes up for the lack of natural instincts in the outfield and the occasional misplay, giving him the ability to play a passable center field. In 2020 Na was mainly limited to DH and only appeared in 47 games in the outfield, all in right. Whether or not this was a precautionary move on part of the Dinos or their internal scouts deciding that his ACL injury sapped him of the ability to play an adequate outfield remains to be seen, though in his limited innings in the outfield he appeared fine.