The Nationals declined Robles' (back) $3.3 million club option for 2024 on Thursday, Andrew Golden of The Washington Post reports.
Robles won't immediately become a free agent, though, because he carries one more year of arbitration eligibility. A former top-10 prospect, the 26-year-old was limited to 36 major-league games in 2023 because of a lingering back injury and owns a disappointing .238/.312/.360 career slash line in 1,801 plate appearances at baseball's highest level.