In what may be a prelude to future changes at the big-league level, Major League Baseball has informed farm-system directors across the league that the Triple-A level will pivot to using the challenge-based Automated Ball Strike (ABS) System in all games at that level, Jesse Rogers of ESPN reports. Currently and for some time, Triple-A games have used the challenge system for weekend contests and full ABS – meaning the call of every ball and strike is automated rather than being determined by the judgments of human umpires – was in place during the week. Now, however, the challenge system will be used for every game. 

The reported memo to farm directors comes not long after MLB commissioner Rob Manfred suggested that the challenge system was the likely path forward at the major-league level. Under Manfred, MLB has on numerous occasions used the minor leagues as a rule laboratory of sorts to test structural changes being considered for the big-league level. Many of those, such as the pitch clock and larger bases, have indeed wound up being implemented in MLB. For now, this appears to be the likely trajectory for the ABS challenge system. 

The ABS challenge system, unlike the full system, still relies on the plate ump to make ball-strike decisions. The wrinkle is that teams can challenge specific ball or strike calls that they deem incorrect. Each team is given a limited number of "incorrect" challenges per game, which incentivizes judicious use of those challenges. In the event of a challenge, the automated system is used to confirm or change the umpire's call. 

Here are more details from Rogers: 

"Additionally, the International League will experiment with teams only receiving two challenges per game instead of three, which has been the norm. That change is being implemented in an effort to reduce the frequency of high-challenge games. The league memo indicates that 89% of fans believe the optimal number of challenges per game is six or fewer; however, almost 40% of Triple-A games featured more than six. In all cases, teams retain the challenge if they are successful."

Here's a look at the challenge system in action, and as you'll see the entire thing plays out quite quickly: 

If the ABS challenge system is adopted in the majors, then the question becomes whether that will be on a permanent basis or as a stepping stone to the full ABS. How soon the challenge system might make its way to MLB is uncertain, but the logistical challenges are substantial given that players and umpires are heavily invested in the process.