Fantasy Baseball Waiver Wire: Sal Stewart leads September call-ups; Payton Tolle thrives in debut

September call-ups aren’t what they used to be, not with active rosters no longer expanding to 40, as was true a few years ago. Instead, teams can promote just two additional players, bringing the roster size to 28.

Those spots will mostly be filled by spare arms to build in extra rest for the more valuable ones during this final stretch of the season — players of little consequence to Fantasy Baseball, in other words. The biggest call-ups already happened in late August, beginning when there were only 45 days left in the regular season. Once we reached the point when new arrivals could preserve their rookie eligibility for next year, there was little incentive to keep them down.

But there are always exceptions, and the biggest this year could be Sal Stewart, who we learned Sunday would be joining the Reds when rosters expand Monday. The 21-year-old always rated highly for his plate discipline and bat skills, but after reaching Triple-A in mid-July, his power production exploded, seeing him homer 10 times in just 38 games.

There wasn’t anything fluky about it. He was hitting the ball with real authority, placing in the 93rd percentile for average exit velocity (93.1 mph) and the 96th percentile for max exit velocity (113.7 mph). Those readings are comparable to Gunnar Henderson, but with a strikeout rate (15.8 percent) that’s comparable to Jose Altuve.

It means Stewart has a chance to be a big contributor in Fantasy, but we all know how difficult the transition to the majors can be for hitters, particularly 21-year-olds with little upper-level experience. It’s also not immediately clear where or how much Stewart will play. He’s a natural third baseman who’s also gotten some exposure to second base in the minors. Those spots are filled by Ke’Bryan Hayes and Matt McLain, respectively, but neither brings much to the table offensively, at least not this year. The Reds are also lacking a dedicated DH, making for three spots that could accommodate Stewart on a part-time basis.

Could he cobble together full-time at-bats between the three? Possibly, if he hits enough. For now, though, I would prioritize Stewart only in leagues of some size, particularly Rotisserie formats with an extra middle and corner infield spot to fill. Basically, if Jordan Lawlar is worth adding in your league, then Stewart is as well..