NEW YORK - The Nationals announced this morning that right-hander Jordan Zimmermann has been scratched from his scheduled start today with flu-like symptoms. Tanner Roark, who had been set to start the Nats' home opener tomorrow, will now start today's series finale against the Mets. A chest cold has been working through the Nats clubhouse all spring, and Zimmermann is apparently the latest to catch a bit of it. Roark was scheduled to start the Nats' exhibition game against the Tigers last Saturday before it was rained out. He threw a "heavy bullpen" instead, but because he last threw on Saturday, he'll now be pitching on normal rest today.