Aaron Parker went 3-for-5 in his Arizona Fall League debut Saturday, giving the Blue Jays a catching prospect worth watching this fall.

And he did it with an old teammate in the same dugout. Arjun Nimmala, the Angels' No. 1 prospect and once Toronto's top prospect, is also playing for Mesa.

The AFL has only six teams, so prospects from five organizations get pooled on each roster. Toronto's entire group landed with the Mesa Solar Sox, and so did the Angels' group.

Parker and Nimmala shared a clubhouse briefly at Double-A New Hampshire this year. Then the deadline hit, and the shortstop went to Anaheim in the José Soriano trade.

Saturday's loss belonged to the catcher, at least on the stat sheet. He doubled, drove in a run and scored once, while Nimmala's lone hit was an RBI double.

That's the AFL in a nutshell. A sixth-round pick out of UC Santa Barbara outhitting the former first-rounder in his own lineup.

A 19-homer season has the catcher eyeing Triple-A Buffalo

The bat is real. Parker hit .253/.347/.467 this season with 19 home runs and 48 RBIs.

By late August, he'd reached 16 homers. That was the most by a Jays catching prospect since Travis d'Arnaud hit 16 in 2012.

Yet he isn't among Toronto's Top 30 prospects at MLB Pipeline. That's a miss, plain and simple, for a catcher who's produced over three straight minor-league seasons.

The catch, pun fully intended, is health. Injuries held him to 63 games at High-A Vancouver in 2025 and 87 games this season.

That's a big part of why he's in Arizona. More at-bats now set up a 2027 where he could push for a job in Buffalo.

The big-league path isn't wide open. Alejandro Kirk and Brandon Valenzuela give Toronto solid depth behind the plate.

But catching depth is like a spare tire. Nobody thinks about it until they're stuck on the shoulder of the highway needing two.

Jake Cook, Jake Casey, Fernando Perez, Brandon Barriera, Jake Bloss, Yondrei Rojas and Gilberto Batista round out Toronto's Mesa group.

Mesa is back on the field Sunday. Parker gets a month to prove the debut wasn't a fluke, and Nimmala gets a month to remind everyone why he went in the first round.