According to the Rangers, the MRI results are expected on Saturday. Rangers assistant general manager Thad Levine says that Darvish would have the exam and then be examined by team physician Dr. Keith Meister.
After the game, Darvish said the injury wasn't serious after his arm failed to loosen up.
"This is nothing to worry about," Darvish said. "Today, when I was throwing in the bullpen, it started to feel like it was tightening up, so from then on I started to throw without putting too much effort.
The 28-year-old, three-time All Star went 10-7 with a 3.06 ERA and 182 strikeouts last season for the Rangers, missing the last seven weeks of last season with mild inflammation in his right elbow.
- Scooby Axson