Nate Karns allowed three runs on seven hits over six innings and had six strikeouts in his start Friday at Double-A Harrisburg.
Karns didn't make it out of the first inning in his previous outing, so it was a much needed return to form. If Ross Detwiler is placed on the disabled list, Karns could become an option for the Nationals. He currently owns a 4.38 ERA and 46 strikeouts over 39 innings (eight starts) at the Double-A level.
Dan Haren was pulled in the fifth inning after giving up seven runs Sunday in a loss to the Padres.
Haren suffered an ankle injury during his last start and may not be completely healthy. He allowed three runs in the first inning and gave up a pair of home runs to Will Venable and Kyle Blanks. Haren is in position to bounce back with a matchup against the Phillies next week.
Bryce Harper (knee) is not in the Nationals' lineup Sunday.
Harper is still feeling banged up from last week's collision with the Dodger Stadium outfield wall. It's his left knee that has been bothering him most. He'll try to return to the Nationals' starting lineup on Monday.
Jordan Zimmermann took a tough-luck loss Saturday, giving up two runs -- one earned -- over eight innings against the Padres.
Zimmermann was as good as anticipated in PETCO, striking out six, walking none and scattering seven hits. One of the most underrated pitchers in the majors, Zimmermann is 7-2 with a 1.62 ERA and 45/9 K/BB rate in nine starts over 66 2/3 innings.
Jayson Werth is going to Chicago to see another specialist regarding his tight right hamstring.
Werth suffered a setback in his rehab Wednesday when he felt some tightness in his hamstring during a game at High-A Potomac. He saw a doctor in New York on Saturday, and he'll see another one in Chicago early next week. He is still hoping to return to the Nationals' lineup by Friday but that seems unlikely to happen.
Bryce Harper will miss Saturday and likely Sunday's game as well because of a bruised left knee.
Harper is still feeling the effects of running into the Dodger Stadium outfield wall on Monday night and is getting a few days to recover in San Diego before the Nationals head to San Francisco. Harper underwent an MRI on his abdomen on Friday, which came back clean.