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Ross Detwiler threw a clean bullpen session on Saturday afternoon and, barring any issues in the meantime, was cleared from his slight oblique strain to make his next start on Tuesday against the Baltimore Orioles in Washington. The Nationals had been pleased with Detwiler’s progress over the past week but Saturday’s bullpen session was the final hurdle to restoring their rotation.

Under the watchful eye of pitching coach Steve McCatty, Detwiller threw in the bullpen in right field. He sat for five minutes halfway through the session to simulate the up-and-down nature of an inning. Detwiler pushed himself to test the injury and was pleased with the results.

“I threw a little harder today than I normally would,” Detwiler said. “I wasn’t held back at all by myself. I proved to myself today that I was healthy and ready to go.”

Added McCatty: “He threw the ball very good. No problems.”

Detwiler, who was off to a strong start with a 2-4 record and 2.76 ERA, left in the third inning of his May 15 start in Los Angeles with spasms in his lower back and missed his next start, on Monday. Zach Duke started in Detwiler’s place on Monday and, with the benefit of having Thursday off, the Nationals needed to fill Detwiler’s spot in the rotation just once. Detwiler’s absence created ripple effects on the bullpen, which had to carry the load and added extra relievers this week to deal with the subsequent toll.

Tuesday will be the first day the Nationals would need him back in order to prevent any starters from pitching on short rest. As a result, Detwiler will have received 12 days off between his starts. Stephen Strasburg will start on Sunday in the series finale against the Philadelphia Phillies and Gio Gonzalez on Monday against the Orioles, both on regular rest. Detwiler will now be sandwiched between Gonzalez and Jordan Zimmermann, who will start Wednesday, in the rotation.

Detwiler played catch in San Francisco and did nothing but receive treatment during the four-game series in San Diego. He played catch again Thursday without any issues.

“He threw the ball well,” Manager Davey Johnson said of Saturday’s bullpen session. “Felt good. [McCatty] was impressed.” Added Detwiler: “Anytime you get healthy again it’s definitely going to be a relief.”