SIOUX CITY EXPLORERS PRESS RELEASE
Phone: 817.739.3693
Website: xsbaseball.com
FOR IMMEDIATE RELEASE
December 16, 2025
THOMAS RETURNS AND ROSARIO DEBUTS
PITCHING STAFF ADDITIONS FILL THE HOLIDAY LIST FOR THE X’S
SIOUX CITY, Iowa – The Sioux City Explorers have announced that the team has signed returning right-handed pitcher Tahnaj Thomas and newcomer Julio Rosario to contracts for the 2026 season. The pair are the 11th and 12th roster additions of the offseason for the Explorers and Manager Steve Montgomery.
Tahnaj Thomas returns to Sioux City for a second season after the native of the Bahamas was acquired via trade from the Milwaukee Milkmen on August 22 of last season. Thomas was a key piece in the Explorers late season push for the best record in the American Association and the eventual West Division crown in 2025. The right-hander went 1-0 in relief pitching in four games over 3.1 innings, surrendering one earned run on three hits with a pair of strikeouts. With Milwaukee, the hard-throwing right-hander appeared in 28 games last season for the Milkmen, making one start. Thomas posted a 5.23 ERA across 31 innings with Milwaukee, striking out 34 batters and walking 20. The Milkmen signed Thomas for the 2024 season, but he did not pitch for the team until the 2025 season.
Thomas was originally signed as a shortstop by the Cleveland Indians organization in 2016 as an international free agent. He made his professional debut in 2017 and transitioned fully to pitching during the season. Thomas was traded to the Pittsburgh Pirates in November 2018 where he spent five seasons, reaching Double-A in 2023. His last season in the Pirates system was in 2023 where he went 4-2 with Double-A Altoona in the Eastern League. Thomas would make 36 appearances and would record three saves in 44.2 innings before electing free agency in November of 2023. Thomas posted a 4.87 ERA with a 1.579 WHIP in 2023.
Thomas made his Double-A debut in 2022 where he posted a 3.02 ERA with 52 strikeouts and three saves in 50.1 innings. He made 36 appearances out of the Altoona Curve bullpen while making one start. Thomas was second on the team in relief appearances and finished with a 1.263 WHIP on the season. The body of work during the 2022 season earned Thomas an invite to the Arizona Fall League following the MiLB season, where he struck out 11 in 9.1 innings. Thomas spent the 2021 season with High-A Greensboro, finishing with 16 starts, the second highest on the club and striking out 62 batters over 60.2 innings.
In 2020 Thomas did not play as the MiLB season was shut down, but he made his first Pittsburgh farm system appearance in 2019 with Rookie Advanced Bristol. He worked 48.1 innings with a 3.17 ERA striking out 59 batters in 48.1 innings. Over his final six starts, Thomas dominated with a 1.86 ERA and 33 strikeouts in 29 frames, including a memorable outing where he hit 101 mph on the radar gun for the first time.
Thomas would spend the 2017 and 2018 season with the Cleveland Indians organization. He spent 2018 with the Indians in the Arizona League, pitching in 19.2 innings with 27 strikeouts in eight games. He would make six starts and finish with a 4.58 ERA with no record. In 2017, Thomas split time between Rookie stops in the Arizona League and the Dominican Summer League. He pitched a combined 16 games over 38.1 innings with 34 strikeouts, making 13 starts. He went 0-5 and finished with a 5.63 ERA for his rookie season.
The native of Freeport, Bahamas has also pitched on the international stage with Team Great Britain in the 2023 World Baseball Classic. The righty pitched a shutout inning in Great Britain’s final qualifying opportunity against Spain. Thomas locked down Team Spain in the 10th inning and Great Britain would walk it off with former Gary SouthShore Railcats Alex Crosby delivering the go-ahead RBI.
Julio Rosario comes to Sioux City after three seasons with the Kansas City Royals organization. Rosario was signed by Kansas City on November 21, 2022, as an international free agent and was sent to his native Dominican Republic for his professional debut in 2023. The right-hander reached class A Columbia in the Carolina League in 2025. He would appear in 30 games in relief with five saves and a 4.35 ERA in 49.2 innings. Rosario struck out 51 and posted a 1.289 WHIP for the season. He was particularly solid in the month of May, allowing just two earned runs in 13 innings and for the month of June, pitching another 13 innings, he surrendered four earned runs.
In 2024 Rosario started the season in the pen for the Royals club in the rookie-level Arizona Complex League. He went 4-2 with a 2.45 ERA with three saves over 29.1 innings. He struck out 40 while leading the team in games pitched and in saves, and finishing second in strikeouts. Rosario began the season working 10 scoreless innings over four appearances, and he closed out the last full month of the season yielding one earned run in 11 innings in August.
Rosario would earn a shot at A-level Columbia in August of 2024 and would go 2-0 in seven games with a 2.40 ERA. Rosario would punch out 16 in 15 innings with a 1.200 WHIP for Columbia. He picked up his first win for Columbia, tossing three scoreless relief innings on August 8 against Kannapolis (Chicago White Sox).
Rosario would go 1-4 with a 3.18 ERA in 2023 in 12 games making three starts with the Royals Blue of the Dominican Summer League. The right-hander allowed more than one run only twice in 12 games and walked just three over his final 15.1 innings to go along with six walks all season in 28.1 innings. For his career, the right-hander is 9-13 with a 3.38 ERA in 122.1 professional innings with 127 strikeouts and a 1.234 WHIP. Rosario, 23, hails from Azua, Dominican Republic.
2026 Players signed:
INF Cameron Bufford
C Caden Matlon
RHP Ryan Beaird
RHP Trey Morrill
LHP Ben DeTaeye
C Dillon Tatum
IF Braulio Vasquez
IF Alberto Osuna
OF Yeison Asencio
IF Elliot Good
RHP Tahnaj Thomas
RHP Julio Rosario
The Explorers are set to open their 33rd season in Siouxland on the road on Friday night, May 15, against the Chicago Dogs. The club will celebrate opening night at Lewis and Clark Park on Friday night, May 22, against the Lincoln Saltdogs. Ticket packages for the 2026 season along with sponsorship and partner opportunities are available now by calling the Explorers front office at 712-277-WINS. Follow the Explorers social media channels and the club’s website xsbaseball.com for off-season news and updates.
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