Which Blue Jays prospect will debut first in 2026?

Last season at triple-A Buffalo, the left-hander compiled a 5.06 ERA and 1.51 WHIP across 18 appearances (10 starts). Walks were mostly to blame for his subpar performance (5.1 BB/9), a mark that figures to come down going forward.

Last year’s usage as a starter and reliever may indicate more of a swing role for Macko, not unlike the role that Eric Lauer held in Toronto last season. It will likely take an injury to a starting pitcher – or Lauer – to get Macko up to Toronto. There’s a good chance that he could be the first starter called upon from Triple-A, providing he improves on last year’s numbers in the early portion of the season.

Potential debut: early-mid season as an injury replacement

RJ Schreck

Also acquired from Seattle, Schreck has done nothing but hit since joining the Blue Jays organization.

The former Vanderbilt Commodore followed up an excellent 28-game stretch with double-New Hampshire with an even better showing through his first 41 games in 2025 (.914 OPS). This earned him a call-up to Triple-A Buffalo, where he was the affiliate’s most consistent offensive player in the second half of the season, slashing .242/.392/.435 across 58 games.

The 25-year-old may not have the loudest tools in the system, but his patient approach (career .386 OBP) falls right in line with the type of offensive player the Blue Jays covet. As a left-handed hitter, Schreck excels against righties (.868 OPS in 2025), although he certainly holds his own against lefties as well (.808 OPS). He is average defensively and as a baserunner, making it clear that his offensive numbers will have to carry him to the big leagues.

Depending on who the Jays may add to their outfield this offseason, it’s not hard to imagine Schreck pushing for playing time in the outfield in 2026. He may end up proving to be an upgrade over Nathan Lukes, potentially settling into a platoon role against right-handers. Due to his subpar defense and baserunning, the Blue Jays probably won’t carry him as a fourth outfielder unless he has a chance for significant at-bats.

Potential debut: early-mid season

Ricky Tiedemann

The Blue Jays appear poised to enter the season with an impressive collection of starting pitching, with newcomers Dylan Cease and Cody Ponce joining Kevin Gausman, Trey Yesavage, Jose Berrios, and Shane Bieber. While there may not be a spot early on in 2026, the long-overdue debut of Tiedemann should be in the cards at some point next season.

It wasn’t long ago when Tiedemann was in line to have a Yesavage-type of impact in Toronto, frequently mentioned among the top pitching prospects in baseball. His 2024 Tommy John surgery, as well as a myriad of other ailments, has defused the hype train over the last couple of years. It’s easy to forget that he’s still just 23 years old and could eventually provide the club with their only left-handed starter.

Before a major league debut is possible, the 2021 3rd rounder will have to show that he’s recovered from TJ, an injury that knocked him out for the entire 2025 campaign. Barring injuries to their current starters, the club should be in no hurry to move Tiedemann up to the big leagues, making it unlikely that he debuts any earlier than mid-season.

Potential debut: mid-to-late season

Javen Coleman

The first three names on this list should come as no surprise, with all having at least some experience at the highest minor league level. A dark horse candidate that could find his way to the big leagues before too long could be Javen Coleman, an up-and-coming left-handed relief prospect who really impressed in 2025.

The former LSU Tiger spent the year split between single-A Dunedin and high-A Vancouver, producing a combined 3.00 ERA, 1.13 WHIP and 14.2 K/9. His second half with Vancouver was particularly impressive, dominating to the tune of a 1.30 ERA and 40:6 K/BB ratio in 25.2 innings.

Relievers have a higher chance of moving rapidly through the minor league system, especially those that have knockout strikeout stuff from the left side, like Coleman. He’s also 24 years old, which should help the Blue Jays feel comfortable moving him along aggressively.

The club could use another left-handed reliever, with Mason Fluharty, Brendon Little, and Justin Bruihl being the only pure southpaw relievers on the 40-man roster. Coleman should start the year in Double-A New Hampshire, but his performance could make him a quick mover through the upper minors.

Potential debut: mid-to-late season