Cuas spent his debut season of 2015 with the rookie–level Helena Brewers, hitting .260/.319/.430/. with 7 home runs and 40 RBI. He spent the 2016 season with the High–A Brevard County Manatees, playing in 120 games and hitting .170/.263/.240 with 4 home runs and 27 RBI. Cuas split the 2017 season between the Single–A Wisconsin Timber Rattlers and the High–A Carolina Mudcats, hitting a cumulative .187/.277/.321 with 5 home runs and 28 RBI.[7]
Cuas was converted to a pitcher prior to the 2018 season.[8] He opened the season with Wisconsin, going 2–0 with an 8.38 ERA over 19+1⁄3 innings before being released on July 10.[9]
Long Island Ducks
Cuas signed with the Long Island Ducks of the Atlantic League of Professional Baseball and finished the 2018 season with them, going 2–1 with a 2.38 ERA and 17 strikeouts over 22+2⁄3 innings. Cuas opened the 2019 season back with Long Island.
It was with the Ducks that Cuas began pitching sidearm. Cuas had been throwing sidearm while warming up until, on the advice of Ducks teammate Francisco Rodríguez, he began to work on throwing sidearm full-time.[10]
Arizona Diamondbacks
On May 25, 2019, Cuas was signed to a minor league contract by the Arizona Diamondbacks.[11] Between the Low-A Hillsboro Hops, the Single-A Kane County Cougars, and the High-A Visalia Rawhide, Cuas posted a combined 6–3 record with a 1.60 ERA and 25 strikeouts over 45 innings.[7][12] Cuas was released by Arizona on May 22, 2020, and did not play in 2020 due to the cancellation of the Minor League Baseball season because of the COVID-19 pandemic.[13] Cuas took a job as a FedEx delivery driver during the day and trained with his younger brother in a park in Brooklyn at night.[10]
On May 30, Kansas City selected Cuas' contract and promoted him to the Major Leagues for the first time.[17] He made his Major League debut the following day against the Cleveland Guardians.[18] He struck out the first batter he faced, Oscar Mercado, and retired the next two hitters in order for a perfect inning of relief.[19] On August 9, Cuas recorded his first career save after pitching a scoreless 2⁄3 of an inning against the Chicago White Sox.[20]
On July 31, 2023, the Royals traded Cuas to the Chicago Cubs in exchange for Nelson Velázquez.[22] In 27 appearances for the Cubs, he compiled a 3.04 ERA with 19 strikeouts across 23+2⁄3 innings pitched.
Cuas made nine appearances for Chicago in 2024, struggling to a 7.43 ERA with 14 strikeouts across 13+1⁄3 innings pitched. On June 16, 2024, Cuas was designated for assignment by the Cubs.[23]
Toronto Blue Jays
On June 23, 2024, Cuas was claimed off waivers by the Toronto Blue Jays.[24] In 4 games for Toronto, he struggled to a 9.00 ERA with 3 strikeouts over 3 innings. Cuas was designated for assignment by the Blue Jays on September 5.[25]