loading

News

Under the Radar International MLB Prospects Who Could Make Their Big League Debut in 2026

The minor league season is underway, with the Triple-A International League and Pacific Coast League already in action. Double-A, High-A and Single-A have also begun play.

While many international prospects on Top 100 lists are expected to make their MLB debuts in 2026, here’s a look at several players who are not currently on those lists but could make the jump this year.

Antwone Kelly, P, Pittsburgh Pirates – The 22-year-old flamethrower has been one of the fastest-rising pitching prospects in the Pittsburgh Pirates system over the past year. After opening 2025 in High-A, he earned a promotion to Double-A following a dominant start. He posted a 3.00 ERA in 48 innings with 46 strikeouts for Double-A Altoona.

Kelly also served as the ace for the Netherlands in the World Baseball Classic, starting against Venezuela and allowing two runs in three innings against the eventual champions.

Previously sitting in the low-to-mid 90s, Kelly’s velocity has jumped significantly. He now regularly touches 98-99 mph and has reached 101 mph. He opened the 2026 season in Triple-A Indianapolis and is one step away from becoming just the fourth Aruban pitcher in MLB history — and the first to debut in the 21st century.

Daniel Espino, P, Cleveland Guardians – The former top prospect from Panama who moved to the United States during high school has battled significant injuries throughout his career. After missing most of 2022 with a shoulder injury, Espino underwent surgery that sidelined him for all of 2023 and again in 2024.

Following nearly 3 1/2 years away, Espino returned to game action on Sept. 20, 2025. He recorded two-thirds of an inning, allowing three runs with one strikeout. He later impressed in the Arizona Fall League, tossing 4 2/3 scoreless innings with seven strikeouts.

Now with Triple-A Columbus, Espino has transitioned into a relief role. In his 2026 debut, he threw a scoreless inning and topped out at 95.3 mph. If he can stay healthy, his arsenal could earn him a spot in the Cleveland Guardians bullpen this season.

Garrett Hawkins, P, San Diego Padres – The Canadian right-hander broke out in 2025 after missing the previous season following Tommy John surgery. He dominated at High-A before earning a promotion to Double-A San Antonio, where he continued to excel.

In 16 innings at Double-A, Hawkins posted a 1.69 ERA with 20 strikeouts. Featuring a mid-90s fastball with elite underlying metrics, he has positioned himself as a strong call-up candidate. He began 2026 at Triple-A El Paso, though his stay there may be brief.

Adam Macko, P, Toronto Blue Jays – Macko’s path to this point has been unique. Born in Slovakia, he developed interest in baseball before moving to Ireland at age 12 and later to Canada.

Initially developed as a starter, Macko transitioned to a relief role in 2025 at Triple-A Buffalo. After posting a 5.19 ERA as a starter, he improved to a 3.99 ERA out of the bullpen while increasing his strikeouts to 11.7 per nine innings.

He also represented Canada in the World Baseball Classic, throwing 2 1/3 scoreless innings with four strikeouts to help the team reach a historic quarterfinal.

Macko has opened 2026 with 4 1/3 scoreless innings and 5 strikeouts. A continued strong showing could earn him a call-up to the Toronto Blue Jays. His debut would be historic, as he would become the first MLB player born in Slovakia since its independence in 1993.

Abimelec Ortiz, 1B, Washington Nationals – Acquired in a winter trade, Ortiz could factor into the Washington Nationals plans sooner rather than later, particularly given the team’s lack of a clear everyday first baseman.

Ortiz broke out in 2025 in the Texas Rangers organization. After a slow start at Double-A, he posted a 1.082 OPS with seven home runs and 17 RBIs, earning a promotion to Triple-A Round Rock. He continued to hit at that level, recording a .953 OPS with nine home runs and 33 RBIs in 41 games.

He has carried that momentum into 2026, starting 5 for 15 with 7 walks and three RBIs through four games, along with just one strikeout. If that production continues, a call-up could come soon.

Edwin Arroyo, SS, Cincinnati Reds – After missing the 2024 season due to a torn labrum, Arroyo experienced an inconsistent 2025, finishing with a .716 OPS and three home runs at Double-A Chattanooga.

He rebounded in Puerto Rico’s winter league, posting a .896 OPS in 16 games — one of the top marks in a pitcher-friendly environment.

That performance earned him a promotion to Triple-A to begin 2026. Through five games, Arroyo is hitting 7 of 24 with a home run, 4 RBIs and an  .935 OPS, while continuing to provide strong defense.

With offensive questions beyond Elly De La Cruz and Eugenio Suárez, a strong start could put Arroyo in position to contribute in Cincinnati this season.

Miguel Ullola, P, Houston Astros – The 23-year-old from Puerto Plata, Dominican Republic, is entering his second full Triple-A season and is among the top pitching prospects at that level in the Houston Astros system.

Ullola features a fastball that reaches 97 mph and generates significant swing-and-miss. He struck out 131 batters in 113 2/3 innings in 2025 while allowing just 75 hits in the hitter-friendly Pacific Coast League.

Control remains his primary concern, as he has posted a walk rate of at least 5.2 per nine innings each season. He projects as a potential multi-inning reliever at the MLB level.

In his 2026 debut, Ullola carried a no-hitter into the sixth inning, finishing with one run allowed on one hit and seven strikeouts in 5 2/3 innings.

Luis Lara, OF, Milwaukee Brewers – In a system headlined by top prospects Luis Peña and Jesús Made, Lara has flown under the radar. However, the Venezuelan outfielder has established himself as one of the premier defensive center fielders in the minors, winning a minor league Gold Glove in 2025.

His defense is MLB-ready, but his bat has been the question. While he makes consistent contact, he has struggled with quality of contact and power, hitting just 12 home runs combined from 2022-25.

Early in 2026, however, he has shown improved power, hitting two home runs in his first five Triple-A games after hitting just two all of 2025.

With elite defense and speed — including 44 stolen bases in 2025 — added power could accelerate his path to the majors.

Esmerlyn Valdéz, IF/OF, Pittsburgh Pirates – The 22-year-old Dominican entered 2026 somewhat overlooked on Triple-A Indianapolis’ roster, which previously included top prospect Konnor Griffin. With Griffin promoted, Valdéz has emerged as a key player to watch.

He broke out in 2025 at High-A with 20 home runs before earning a promotion to Double-A Altoona. While his power numbers slowed, his plate discipline improved, with an increased walk rate and steady strikeout rate.

Valdéz then starred in the Arizona Fall League, posting a 1.355 OPS with eight home runs, 27 RBIs, 19 walks and just 12 strikeouts.

That performance has carried into 2026. Through five games, he owns a .983 OPS with a home run and just two strikeouts in 20 plate appearances. His contact rate has improved significantly, and he continues to hit the ball with authority.

If his power translates at Triple-A, the Pirates could consider promoting him this season.

Brandan Bidois, P, Pittsburgh Pirates – Twenty-four Australian pitchers have reached MLB, with Grant Balfour and Liam Hendriks among the most notable.

Bidois is aiming to join that group after a breakout 2025 season. He posted a 0.86 ERA with 27 strikeouts in 21 innings at High-A before continuing his dominance at Double-A Altoona with a 1.08 ERA and 26 strikeouts in 25 innings.

After a promotion to Triple-A Indianapolis, he added 13 scoreless innings with 15 strikeouts. Featuring a fastball that reaches 99 mph, Bidois enters 2026 with significant momentum and could soon earn a call-up as he looks to establish himself at the highest level.

Photo: Daniel Espino returned to action after missing several years due to injury. (AP Photo)

Table of contents

Navigation

Subscribe to our Newsletter!

Subscribe to our newsletter for exclusive content, breaking news, and special offers.

Follow Us !
Related Articles
Explore Our Store!

Our Store

Shop now and join a community that plays, supports, and lives baseball.

Check out our Memberships!

Become a Member

Join the ultimate baseball community and unlock exclusive perks like early access, live chats, giveaways, and behind-the-scenes content. From free Global Fan access to VIP Hall of Fame experiences, there’s a membership level for every true baseball fan.

SUBSCRIBE TO OUR NEWSLETTER

Stay in the Know, Don’t Miss a Beat!

Get the best of World Baseball Network delivered straight to your inbox.
Subscribe to our newsletter for exclusive content, breaking news, and special offers.

World Baseball Network (WBN), a certified Service-Disabled Veteran-Owned Small Business (SDVOSB) in the USA and a member of the National Veteran-Owned Business Association (NaVOBA), as well as partners with the Federazione Italiana Baseball Softball (FIBS), Italy’s leading baseball organizer. WBN is also a member of the Society of American Baseball Research (SABR), dedicated to baseball history and statistics.