The South Korean baseball league on Thursday touted the accuracy and consistency of its new automated ball-strike system (ABS), saying differences among stadiums aren't as significant as some teams have claimed. The Korea Baseball Organization (KBO) said it conducted accuracy tests for the ABS, implemented for the first time this season, at all nine ballparks from April 8 to 30. League officials set up a pitching machine on the mound and had it fire balls at a memory foam board behind the plate with the strike zone drawn on it. The ABS made calls, using the tracking system installed at each stadium, based on the pitches hitting different spots on the board, and KBO officials then measured how accurate those calls were. According to the KBO, ABS calls were off by an average of 4.5 millimeters horizontally, and 4.4 millimeters vertically. In terms of the horizontal zone, calls at Gocheok Sky Dome in Seoul were missed by the largest margin at 5.8 mm, and Hanwha Life Eagles Park in Daejeon had the smallest mar gin of error with 3 mm. As for the vertical zone, Jamsil Baseball Stadium in Seoul had the largest margin of error at 6.7 mm, compared to the smallest margins of 2.5 mm at Gocheok and at Daegu Samsung Lions Park in Daegu. In a statement, the KBO said it decided to carry out these tests amid growing complaints from teams that there were substantial differences in the strike zone among ABS systems at different stadiums. "With these results, we were able to confirm that the ABS systems across the league have been making consistent calls," the league said. "We have dedicated operators testing the tracking systems four hours before every game in order to ensure consistent strike zones at every stadium, even though tracking cameras may all be set up at different locations or at different angles." Colloquially called "robot umpires," the ABS uses tracking technology to make ball-strike calls and delivers them to the home plate umpire through an ear piece. Teams can also follow those calls in real time from their dugouts. The KBO said the ABS had only missed 21 out of 55,026 pitches thrown through 185 games as of Wednesday. The league added that it will open up a new website where teams can review all official ABS-related data before the end of May. With the ABS in place, the KBO expanded the strike zone by 2 centimeters on either side of the home plate. Major League Baseball widened the zone by 2.5 cm on each side when its minor leagues adopted the ABS in 2022. The top of the ABS strike zone has been set at 56.35 percent of a hitter's height, and the bottom is at 27.64 percent. Source: Yonhap News Agency