MLB's runner-on-second in extras rule reportedly could return; league testing ball-strike challenge in minors
Korean baseball league introduces automated ball-strike system for 2024 as MLB mulls future with robot umps
Automated ball-strike (ABS) system, pitch timer, bigger bases tested at Triple-A
MLB Umpires Missed 34,294 Pitch Calls in 2018. Time for Robo-umps?, BU Today
Automated Ball Strike System: Sugar Land Space Cowboys now able to challenge robot umpire calls at Constellation Field - ABC13 Houston
Jacksonville Jumbo Shrimp use Automatic Ball-Strike System
Robots in Baseball? The Possibility of an Automated Ball Strike System
Triple-A's Ball/Strike Pitch Location Challenge System Update and a Minor League Ejection in OKC
Worcester Red Sox are preparing for robotic ball-strikes system coming
Columbus Clippers, Triple-A baseball learn new challenge system