Nationals activated RHP Ryan Mattheus from the 15-day disabled list. Mattheus missed a little over three weeks due to tightness in his right shoulder. The 27-year-old has registered a 2.40 ERA and 1.27 WHIP through 30 innings this season.

Ryan Mattheus (shoulder) threw a successful simulated game Saturday and is slated to be activated from the disabled list early this week. "He threw the ball fine," said Nationals manager Davey Johnson. "His velocity still is not quite where it was before he got hurt." Mattheus hasn't pitched since August 25 due to right shoulder tightness.

Ryan Mattheus (shoulder) threw another successful bullpen session Wednesday. He threw another 25 pitches -- the same number he threw Sunday. "[The bullpen session] was great. Better than the first one," Mattheus said. "The ball is coming out real good. I had no issue with the arm, which is the biggest thing. ... I let it go a little bit more and it felt game like. My stuff was really good." Mattheus is scheduled for a simulated game this weekend before being activated early next week.

Ryan Mattheus (shoulder) is scheduled to throw a bullpen session on Sunday. Mattheus hasn't pitched since August 25 due to right shoulder tightness. The Nationals are still hopeful that he will be able to make an appearance or two before the end of the season. The 27-year-old right-hander had a 2.40 ERA and 11/14 K/BB ratio over 30 innings prior to the injury.

Nationals placed RHP Ryan Mattheus on the 15-day disabled list with right shoulder tightness. Mattheus has been battling the discomfort for over two weeks and will now rest up until mid-September. The righty has a 2.40 ERA and 1.27 WHIP so far this season.

Ryan Mattheus was pulled from Thursday's game due to tightness in his right shoulder. Mattheus is considered day-to-day for now, but will probably undergo a range of precautionary tests. The right-hander has a 2.40 ERA and 1.27 WHIP on the year.

Ryan Mattheus returned to action on Saturday August 20.

Ryan Mattheus was pulled from Thursday's game after feeling tightness in his right shoulder. Mattheus did not throw a pitch in the game, as he felt the discomfort on one of his warmup tosses. The 27-year-old right-handed reliever is considered day-to-day.