Jansen is a bit behind in Red Sox camp due to an offseason illness, Jen McCaffrey of The Athletic reports.
Jansen had to put a pause on his winter workouts because he and his family got sick. However, there's plenty of time for the veteran reliever to play catch-up and be at or near 100 percent come Opening Day. He inked a two-year, $32 million free-agent contract with Boston in December and projects to serve as the club's primary closer in 2023.