Martinez said that Gio Gonzalez would throw on Monday in the series opener with the Orioles and Hellickson would get his regular rotation start on Tuesday.
Hellickson is 1-0 with a 2.13 ERA over seven starts this season, only one of which has gone beyond six innings. The veteran has thrown 38 innings in his first season with the Nationals, striking out 31 while walking just six.
Grace set for rehab assignment Left-handed reliever Matt Grace is leaving Sunday for a rehab assignment on Monday at Double-A Harrisburg. The 29-year-old, in his fourth season with the Nationals, continues to progress from left groin soreness that landed him on the 10-day DL on April 21.
"He threw 25 pitches the other day in a sim game and looked good," Martinez said. "So we'll see what happens on Monday. He might just need one [rehab assignment]. We'll reevaluate when he gets through."
The Nationals have had more than their fair share of injuries already this season. Grace is one of 12 Washington players on the DL -- the most in the Majors -- and yet the Nationals are playing their best baseball so far this season. They've won 10 of their last 15 games and, since April 29, are an MLB-best 16-6.
Whether that speaks to the depth of the club, its versatility, or superior managing is debatable, but Martinez gives all the credit to those who put it on the line every day.
"I [attribute] all that to the players," Martinez said. "They go out there and they play; they perform. They've done well. I've said this time and time again, I've asked them to do things they might not be comfortable doing and they've done really well.
"We just try to stay positive with them and put them in situations where they're going to succeed."
Glenn Sattell is a contributor to MLB.com based in Miami.