WASHINGTON -- The Nationals made a switch in their pitching rotation on Thursday. Left-hander John Lannan, who was scheduled to pitch on Saturday against the Pirates, will now throw against Pittsburgh on Friday on five days of rest.

Left-hander Matt Chico, who has been struggling in his last three starts, will get an extra day of rest and throw on Saturday against the Pirates.

"We wanted to give Chico an extra day to relax some more and have some time to work with [pitching coach] Randy [St. Claire] and try to get things in order," manager Many Acta said.

In his past three games, Chico has allowed 16 runs in 13 innings and has seen his ERA soar to 6.68. Chico reiterated on Tuesday that he is pressing and there is nothing wrong off the field or mechanically on the mound. He said he has to take a step back and relax on the mound.