The Cincinnati Reds have established the strongest record in MLB’s 2026 ABS challenge system, posting the league’s highest combined success rate near 64 percent through late-season data, well ahead of contenders like the Diamondbacks and Tigers. Their edge stems from disciplined usage by catchers such as Tyler Stephenson, who has converted roughly 73 percent of attempts, and selective batter challenges led by players like Sal Stewart, allowing the club to overturn calls efficiently without exhausting opportunities early. This strategic approach under manager Terry Francona has produced consistent results across hundreds of attempts, reflected in the market’s heavy weighting toward Cincinnati. A late injury to key personnel, shifts in pitching staff usage, or unusual variance in final weeks could narrow the gap, though the Reds’ sustained leadership makes significant erosion unlikely before season’s end.