CINCINNATI -- Nationals right-hander Jordan Zimmermann was scratched for Monday's start with Class A Potomac because of a stiff neck. He will be evaluated Tuesday.
Zimmermann, who has missed most of the season because of elbow reconstruction, has pitched in three rehab games and hasn't allowed an earned run in nine innings.
Zimmermann is tentatively scheduled to return to the big league by August. Once he returns, Zimmermann and right-hander Stephen Strasburg are expected to form a 1-2 combination in the rotation.