He will have a bullpen session on Wednesday and then join Double-A Harrisburg to continue his rehab assignment on Friday. Chico has already pitched three games for Class A Hagerstown this season, giving up three runs in 11 innings.
There is no timetable as to when Chico will return to the Major Leagues. Chico hasn't pitched in a game for the Nationals since May 21, 2008.
"It's just nice to be in a uniform again," Chico said. "Down in Hagerstown, I was sitting around 88, 90 [mph]. I feel like I'm starting to get back to what I used to do -- being able to locate my pitches better."
Chico was the Nationals' best pitcher in 2007, going 7-9 with a 4.63 ERA.
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.