Last year, Jung-ho Kang became the first hitter to make the transition from the Korean Baseball Organization to Major League Baseball. To say it was a success would be a remarkable understatement, as Kang put up a 130 wRC+ on his way to a four win season and a third place finish in the NL Rookie of the Year balloting. Considering that Kang will cost the Pirates a grand total of $20 million, posting fee included, over the five years for which his contract runs, his signing was probably the best transaction any team made in 2015. The Pirates bet on a quality KBO hitter paid off in a massive way.
Thanks to Kang’s success, the door opened for more KBO hitters to follow, and this year, Byung-ho Park and Dae-ho Lee have joined Kang in the big leagues. But it’s not like Kang’s success led to instant riches for the pair; Park got a four year, $12 million deal from the Twins with an option that could push it to 5/$18M, and Lee got a minor league deal that would pay him up to $4 million if he made it to the big league roster and hit all his incentives. Teams were more open to KBO hitters — and in Lee’s case, a KBO hitter who had already made the transition to the more difficult NPB league in Japan — but the contracts suggest plenty of skepticism about the expected production levels from both hitters.
It’s obviously too early to be making any kind of declarations, but here’s what Park and Lee have done in their first six weeks of action.
Park has 22 hits; 12 of them have gone for extra bases. Lee has 13 hits, and five of them have gone for extra bases, but they’ve all been home runs. Between them, they’ve launched 12 home runs in 152 plate appearances; Nolan Arenado currently leads the big leagues with 12 home runs in 145 plate appearances.
Now, they won’t keep hitting bombs at this rate. Lee’s HR/FB rate is a hilarious 46%, and Park is at 28%; the highest sustained HR/FB rate any hitter has put up during the last decade is Giancarlo Stanton’s 26%. Chris Davis, who is generally considered to have 80 power, has had 24% of his fly balls leave the yard during his career. Adam Dunn was at 22%. Chris Carter is at 21%. Bryce Harper and Mike Trout are at 20%. This is the reasonable range for top-of-the-shelf power hitters, and both Park and Lee are surpassing those levels, making it almost impossible to keep hitting for as much power as they have.
But power is also something that is very hard to fake, and the fact that both guys are showing off this kind of power suggests that they’re better equipped to handle MLB pitching than was advertised. While Lee has certainly benefited from being platooned — 60% of his at-bats have come against lefties — and Park’s contact rate might limit his upside even with real power, these guys both look like average-at-worst MLB hitters, and Park is probably a good bit better than that.
Combined with what Kang did in his first year in the big leagues, it seems likely that MLB teams have been overly skeptical of KBO hitters. And the three teams who were willing to make small bets on their ability to hit MLB pitching may get rewarded in a big way.
Dave is the Managing Editor of FanGraphs.
Hyun Soo Kim is batting .478/.538/.522 in limited playing time as well.