Rosario was optioned to Triple-A El Paso on Wednesday.
Rosario was added to the 40-man roster in November to protect him from the Rule 5 draft, and he went 4-for-18 with a run, an RBI, a stolen base and four strikeouts across nine Cactus League appearances this spring. After spending the entire 2021 campaign at Double-A San Antonio, he should progress to the Triple-A level to begin the season in 2022.