The Nationals were forced to scratch Jordan Zimmermann from today’s scheduled start against the Mets when the right-hander came down with flu-like symptoms and now will send Tanner Roark to the mound instead for their 1:10 p.m. series finale at Citi Field. Zimmermann appears to be the latest member of the roster to experience a nasty chest cold that swept through the clubhouse late in spring training and has carried over into the regular season. It’s possible the right-hander will feel well enough to return to start Friday’s home opener against the Braves, though the Nationals won’t know that for awhile.