Yastrzemski was placed on the 10-day injured list Monday with a left hamstring strain, Alex Pavlovic of NBC Sports Bay Area reports.
Yastrzemski sat out Sunday's contest against Boston due to soreness in his hamstring, and his injury is apparently severe enough to warrant a trip to the IL. Manager Gabe Kapler added that Yastrzemski will likely be held out for two-to-three weeks, per Maria I. Guardado of MLB.com. Isan Diaz was brought up from Triple-A Sacramento in a corresponding move.