Warren (elbow) was placed on the 60-day injured list Sunday, Maria I. Guardado of MLB.com reports.
The move to the long-term IL was an eventuality, as Warren underwent Tommy John surgery last May and isn't expected to be available until midseason. The right-hander joined the Giants on a one-year deal last week and has a 3.55 ERA in 32 big-league appearances over his career.