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It’s the most wonderful time of the year …

OK, so maybe using the old Andy Williams tune is overstating things a little, but this early part of October provides such a magnificent confluence of events: the MLB postseason and the start of the Arizona Fall League.

The AFL began its 32nd season on Monday night. As usual, the rosters are chock full o’ prospect talent. At the same time, the Division Series are going on at the big league level and as fans and purveyors of the sport, we’re locked in on that as well. We’ve written about prospects and rookies in the postseason, and as I told folks in this week’s Pipeline Inbox when talking about our internal conversation about Jackson Jobe’s first playoff appearance, we have a kind of parental protective vibe going when the young guys get thrown into the fire.

This cross-section got me thinking about the sheer volumes of players who go from the AFL to the big leagues. The total count is over 3,000 at this point, with three Hall of Famers on the alumni list (Mike Piazza, Todd Helton and Derek Jeter). What I didn’t know, and what I didn’t find anywhere, is what kind of Fall League imprint there was on the eight remaining postseason rosters. So I did a deep dive.

Of the 208 total players on playoff rosters currently, a grand total of 90 of them were on an AFL roster at some point. That’s a robust percentage of 43.3. The National League clubs have an edge, 49-41, with the Phillies and Mets filling more than half of their rosters with Fall Leaguers (14 each). The Yankees top the AL with 13. It’s an impressive list of MVPs, All-Stars and standouts, some of whom are likely to follow Piazza, Helton and Jeter to Cooperstown. Here’s the top 10 list of AFL alum in the postseason, ranked by WAR, with the years they played in the AFL in parentheses:

Mookie Betts (2013), 69.6
Freddie Freeman (2009, 2010), 60.7
Aaron Judge (2014), 52.2
Bryce Harper (2010, 2011), 51.1
Francisco Lindor (2014), 49.7
Giancarlo Stanton (2009), 44.7
Gerrit Cole (2011), 43.3
J.T. Realmuto (2012) ,36.3
Trea Turner (2014), 36.3
Salvador Perez (2010), 35.3

As you can see, the list goes back a while. But there’s a player who was in the AFL even before Freeman and Stanton hit the desert in 2009. Mets reliever Adam Ottavino pitched in Arizona a year earlier in 2008. But perhaps more relevant is that there are six players on those Major League rosters who saw time in the AFL just one year ago, in 2023, led by the aforementioned Jobe and including recently graduated Top 100 prospects Kyle Manzardo and Jace Jung.

The 2022 Fall League produced 11 players on postseason rosters. You’re probably tired of hearing us say this, but this is yet another example of why you should pay attention to what happens in the Arizona Fall League now: This year’s crop will be helping teams win a championship in a relatively short amount of time.