Aguiar will miss the entire 2025 season after undergoing Tommy John surgery, Mark Sheldon of MLB.com reports.
Aguiar ended the season on the 15-day injured list with a right shoulder sprain, but it's the elbow that wound up requiring an operation. The 23-year-old collected a 6.25 ERA and 19:12 K:BB over 31.2 innings covering seven starts for the Reds in 2024. Barring complications during his rehab, Aguiar should be ready for spring training ahead of the 2026 season.