3 potential September call-ups Royals fans are eager to watch in 2025

The Kansas City Royals find themselves in an interesting spot come Sept. 1, 2025. From that date through the end of the season, every MLB team must carry 28 players: 14 position players and 14 pitchers.

For rebuilding clubs, it’s a chance to give prospects valuable reps with nothing to lose. For contenders, it’s an opportunity for fringe veterans or standout prospects to contribute down the stretch, complementing the regulars who’ve carried the load for most of the season.

But the Royals don’t neatly fit either category as August winds down. They’re still in the hunt for a coveted Wild Card spot, doing everything possible to stay alive in the race, but they can’t afford to jeopardize that by rushing up a prospect who isn’t ready—or by folding too early. Layer in the wave of injuries, and it’s tough to find a seasoned veteran who could make a clear positive impact.

From this angle, there isn’t a slam-dunk choice for Kansas City when it comes to adding one position player and one pitcher for the final four weeks of the season.

While names like outfielder Drew Waters, utilityman Harold Castro, and pitcher Joey Krehbiel are getting deserved attention as possible additions, there are also some fresh faces worth considering.

If the Royals were to use this September window to hand out a debut—a player trotting out of the dugout or bullpen for the very first time in a big-league game—who might they choose, and why would that player make sense?

RHP Jacob Wallace

Royals fans shouldn't be kicking themselves if they haven't heard of right-handed pitcher Jacob Wallace.

The Colorado Rockies drafted Wallace in the third round of the 2019 MLB Draft, drawn in by his electric stuff and professional potential. Across his time with both the Rockies and Red Sox organizations, the stuff remained tantalizing—but the walks were a constant problem. Kansas City acquired him in the deal that sent Wyatt Mills to Boston in the winter after the 2022 season, and Wallace has been grinding ever since.

The Storm Chasers activated Wallace from the injured list on Aug. 22, releasing veteran left-hander Dallas Keuchel to make room. The next day, Wallace made his first Triple-A appearance in more than two months against the Columbus Clippers, working a scoreless inning with one hit, one walk, and a strikeout. Overshadowed by Omaha’s 23-run explosion, his outing was just a footnote in the box score—but still a solid step forward in his return.

Wallace may not be the kind of dominant arm who forces the Royals’ hand, but Kansas City’s relief depth is precarious at best. With right-handers Hunter Harvey and Steven Cruz still sidelined—and the bullpen looking exposed when overworked in August—necessity could open the door. Much like Andrew Hoffman’s call-up earlier this season, Wallace might find himself in the right place at the right time.

The walks are down to a manageable level, the strikeouts are still there, and the clock is ticking on Wallace. If not now, when? That’s the question Kansas City will have to confront if they choose to pass him over once rosters expand in September.

RHP Chandler Champlain

It’s been more than three years since the Royals dealt outfielder Andrew Benintendi at the trade deadline, and the return for even half a season of the World Series winner hasn’t yielded much.

Two of the Yankees’ then–top-30 pitchers were included, but T.J. Sikkema has since landed in the Reds’ system, and Beck Way’s “poor control has been unpalatable for three years running,” as FanGraphs’ Eric Longenhagen put it.

The third arm in that trade isn’t faring much better, though right-hander Chandler Champlain at least has some traits that could chart a path to Kauffman Stadium before season’s end.

The USC product has worked exclusively as a starter throughout his professional career, logging no fewer than 22 starts in any season since his debut. While he never profiled as a top-tier prospect, he steadily climbed the ladder and looked serviceable along the way. In 2024, Champlain flashed real breakout potential during his first seven starts with Double-A Northwest Arkansas, posting a 34.5% strikeout rate against just a 5% walk rate over 36 innings.

That dominant stretch earned him a promotion to Omaha, where his first taste of Triple-A was rough—but easy enough to chalk up to growing pains while waiting to see what he could bring in 2025.

Champlain earned a second straight non-roster invite to big-league camp this spring, but his stay was brief. Once viewed as an intriguing starting prospect, the shine that dulled at the end of last season has only faded further. He’s putting up full-season worsts—a 7.88 ERA, 17.8% strikeout rate, 9.3% walk rate, and a host of other concerning metrics. Opponents are barreling his four-seamer at an alarming clip, and his sinker hasn’t provided the kind of support needed to make his fastball package viable.

Champlain has solid control, but he tends to nibble the zone as his outings progress. Early on, he trusts his stuff, but once the velocity dips, his arsenal shifts—and hitters adjust quickly. The expected results climb the deeper he goes, raising the question: if Champlain doesn’t have the stuff to sustain a starter’s workload, why keep forcing him into that role?

If the Royals still believe Champlain has a future as a starter, they wouldn’t be wrong to stay the course. The 26-year-old has logged three quality starts since July 27, the only three he’s had all season.

Still, his inconsistency and pitch mix raise questions about how he might perform in a bullpen role, limited to one or two innings at a time. If Kansas City is looking for another arm to follow a Jonathan Bowlan-type path, Champlain feels like the sensible choice—and a late-season debut out of the bullpen could be the first step in that transition.

C Carter Jensen

With the Royals playing meaningful baseball and a Freddy Fermin-sized hole still lingering behind the plate, it’s time to address the backup catcher spot beyond Luke Maile. And with prospect Carter Jensen tearing it up in Omaha, the moment feels right to call up the fan-favorite and hometown product.

Jensen has been on a tear in 2025, building on a strong 2024 season split between High-A Quad Cities and Double-A Northwest Arkansas. He was a fixture in the Naturals’ lineup while then-top prospect Jac Caglianone was making noise, and looked even sharper after the Florida slugger’s promotion. Across 28 Double-A games, Jensen slashed .292/.360/.420—good enough for Kansas City to bump the 21-year-old catcher up to Omaha.

A learning curve was expected—maybe even preferred—with franchise legend Salvador Perez and Freddy Fermin still forming a steady combo on the 26-man roster. But Jensen had no intention of easing in.

In just 41 games at Omaha, he’s already launched 13 home runs with a 159 wRC+ in the hitter-friendly International League. His bat has made noise both in games and out of them, with Baseball America naming him the best batting practice performer ahead of the 2025 All-Star Futures Game in Atlanta.

Add in his growing comfort calling games behind the plate, and Jensen’s development this season has been nothing short of monstrous.

With Rule 5 eligibility looming this November, the Royals can’t afford to let Carter Jensen’s momentum stall. It’s time to give him meaningful MLB exposure—even late in the 2025 season. He embodies both the future behind the plate and the spirit of Kansas City baseball.

Promoting him now would provide immediate contributions while laying the foundation for long-term stability. In a season where every win matters, the Royals shouldn’t wait to bring their rising star home.

The Royals can’t afford to bring Jensen onto the 26-man roster without a clear plan. He needs consistent playing time—not only to prove himself in the majors but to keep his confidence and development on track.

With Fermin traded at the deadline, Jensen’s path to the 2026 Opening Day roster already feels wide open. But with the way he’s tearing up Triple-A, why not add him to the 40-man a few months early and let the hometown product get his first taste of MLB action?