While we are debating the aging rate, I decided to do a very quick, small sample size comparison between some CBA and MLB greats: the 14 retired CBA hitters with the highest career WAR, and the 14 most recent MLB hitters from the modern era inducted into the Hall of Fame. Why 14? Because I pulled up the top 50 all-time batting WAR leaders on Stats+ and that’s how many guys are inactive.
The players, CBA: Abel Kennedy, Buzzy Rodriguez, Andy Mobley, Abe Caputo, Jeremy Costanzo, Cameron Brasted, Brent Savage, Adam Camarata, Mike Becklin, Mike Watson, Timothee Brandi, Ernie Horton, Jon Wagner, and Steve Nelson. The dudes in Cooperstown: Edgar Martinez, Vlad Guerrero Sr., Chipper Jones, Jim Thome, Alan Trammell, Jeff Bagwell, Tim Raines, Pudge Rodriguez, Ken Griffey Jr., Mike Piazza, Craig Biggio, Frank Thomas, Barry Larkin, Roberto Alomar. For age, I used the round number represented on a player’s career stats page for that respective season (Baseball-Reference for MLB).
Since this is quick, such a small sample, and not really representative of much, I used WAR as the measuring stick. For each player, I looked at their WAR at every age from their final season back to their “never again” year…the one in which they posted a WAR that they’d never reach again.
MLB average “Never Again” age: 35.86
CBA average “Never Again” age: 33.79
MLB average first negative WAR season: 38.63
CBA average first negative WAR season: 35.88
Some random, interesting observations: The CBA list was almost entirely guys that debuted in 2022 (12 of 14), and the four youngest “never again” years belonged to the four players that debuted at the youngest ages (20, 21, 23, 24). The only two guys (Caputo and Horton) that debuted a year later, in 2023, are among that group. In other words, the CBA totals and “fall off a cliff” years benefit from the presence of the majority of the guys debuting as older players (26, 27, 27, 27, 28, 30, 31, 31, 31, and 34) in 2022. If Caputo and Horton are any indicator, the CBA average ages referred to here will get younger in the future, i.e. younger peaks and earlier declines than these current averages.
From the Cooperstown group, there was just one significantly negative season at age 37 or younger (Alomar’s -0.7 WAR at age 36. The next worst was just -0.1). In the CBA, we had a player already retire after their age 31 season (Kennedy), and 6/13 players posted a negative WAR year by age 37—so, there’s half the list. In the CBA, 4/14 “never again” years happened at age 31 or earlier, while there wasn’t a single one before 33 in MLB. Finally, looking at age 37 onward reduces things to a miniscule sample, but the disparity continues: MLB had at least twice as many players post significant seasons (I used 1.2 WAR for CBA and 1.5 for MLB) at age 37, 38, 39, and 40.