Darvish is expected to miss a couple of starts and will start throwing again when the soreness goes away.
"I'm not too concerned," Darvish said to MLB.com. "I think I could throw if I have to today. I'm just taking a precautionary measure."
The team placed Darvish on the 15-day disabled list on Wednesday. He is the 14th player currently on the DL for the Rangers, who have the worst record in the American League.
Darvish is 10-7 with a 3.06 ERA and his 182 strikeouts are fifth in the AL.
- Scooby Axson