New York Mets right-hander Kodai Senga, the major league ERA leader, was diagnosed with a Grade 1 strain of his right hamstring Friday, hours after he was placed on the 15-day injured list.

Senga was removed in the sixth inning of Thursday’s game against the Nationals at Citi Field with an apparent right hamstring injury.

In the meantime, Paul Blackburn is expected to fill the gap in New York's starting rotation.