The New York Mets have placed Jacob deGrom on the 10-day injured list retroactive to July 15 with tightness in his right forearm.

The right-hander felt discomfort Friday while throwing a bullpen session, Luis Rojas said. An MRI hours later showed there was forearm tightness but no structural damage.

Rojas says that deGrom will not throw again until the discomfort goes away.

"I'm frustrated," deGrom said. "I don't know what else to say. I guess it's good news whenever structurally, everything looks good, but ... the level of frustration now is really high."

deGrom is 7-2 with a major-league-leading 1.08 ERA in 15 starts this season despite being hampered by multiple ailments.