We looked at the top-performing hitters in the KBO in last week’s Stat of the Week. This week, we’ll check out the best pitchers in the league to date.

Chang-mo Koo of the NC Dinos won KBO Pitcher of the Month for May, then allowed one run in six innings in his first start in June. He’s 5-0 with an 0.66 ERA so far this season for a first-place team.

Koo seems to be a pitcher who has broken through on the path to excellence. After posting ERAs over 5 in 2017 and 2018, his ERA dropped to 3.20 last season. One key to his success in 2020 is a strikeout-to-walk ratio of nearly 5-to-1 (44-to-9). He’s never had a ratio of better than 3-to-1 in a season.

Koo features a fastball, curveball, slider and split-finger fastball. Opponents are hitting below .200 against each pitch type. They’re 2-for-21 in at-bats ending with the splitter and have missed on 25 of their first 46 swings against it. Koo leads the KBO with a .144 opponents’ batting average, 51 points better than the nearest pitcher.

Koo’s teammates Drew Rucinski and Mike Wright also rank in the top 10 in the league in ERA. This highly-effective starting pitching has powered the Dinos to a 25-7 record this season, easily the best in the league. The team leads the league with a 3.93 ERA.

Though the Dinos pitching has been dominant, the team with the lowest hard-hit rate in the league is the Kia Tigers (the stat measures the percentage of at-bats ending with a hard-hit ball). Their top pitcher is Aaron Brooks, who has a 2.76 ERA (7th in the KBO) and leads the KBO with an 11% hard-hit rate (among pitchers with at least 100 AB against them). Brooks’ teammate, Ki-young Im, ranks fourth in the league in that stat at 13%.

Another KBO standout has been Eric Jokisch of the Kiwoom Heroes, who is 5-1 with a 1.49 ERA. Jokisch’s MLB experience comes from a four-game stint with the Cubs in 2014. This is his second season with the Heroes. He posted a 3.13 ERA last season, which ranked ninth in the league. Jokisch’s success is partly driven by a curveball that has functioned as an important putaway pitch. Opponents are hitting 2-for-31 when an at-bat ends with one.

Jokisch’s teammate Sang-woo Cho has been one of the league’s top closers, notching 7 saves with an 0.79 ERA in 10 appearances. He’s 2 saves behind Jong-hyan Won of the Dinos for the league lead, though Won has a 3.46 ERA. Cho averages upwards of 93 MPH with his fastball in a league that lacks hard throwers. He’s thrown it for a strike 73% of the time and used it to record 28 of the 34 outs he’s gotten.

The best-known MLB starter in Korea is Dan Straily of the Lotte Giants. Straily has a 2.23 ERA, which ranks 4th in the league, but has gone unrewarded, recording one win in seven starts. Opponents hit .441 against Straily’s slider in 2019 with the Orioles. That pitch, previously an important part of his repertoire, has not been solved yet by KBO batters. They’re hitting .190 against it.

Straily leads the league in soft-hit rate, with 25% of the at-bats against him ending in a softly-hit ball. Perhaps these kind of numbers, if maintained for a season, could be Straily’s ticket back to the major leagues.