The Nationals selected Hassell's contract from Triple-A Rochester on Tuesday, Mark Zuckerman of MASNSports.com reports.
Hassell's star has faded since he was viewed as a top-100 prospect a year ago, as he managed just a .241/.319/.328 batting line over 85 games covering three levels during the 2024 minor-league season. However, the 23-year-old is still viewed highly enough that the Nationals didn't want to expose him to the Rule 5 Draft.