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Stephen Strasburg passed his final throwing test this afternoon and will return to the Nationals rotation Saturday night, Manager Davey Johnson said. Strasburg had twice been scratched because of tightness in his right forearm since he last pitched Sept. 8

This afternoon, Strasburg played catch on flat ground, as he would on the day before any start. The difficulty he had loosening up his arm was no longer present. After he finished throwing, Strasburg had a long chat with pitching coach Steve McCatty and head athletic trainer Lee Kuntz. Once the conversation ended, McCatty and Strasburg bumped fists.

Before Strasburg completed his throwing session without any red flags, Johnson said he was “90 percent” certain Strasburg would pitch Saturday. If Strasburg had felt tightness or irritation, Dan Haren would have moved his start up one day and pitched on short rest. Haren volunteered for the duty, but it will not be necessary.

Strasburg’s latest brush with injury started Sept. 13. On the day before a scheduled start, he felt irritation in his right forearm. Given the care with which the Nationals have handled Strasburg since his Tommy John surgery in 2010, Strasburg pain raised alarms.

The Nationals determined Strasburg’s problem was strictly muscular and not related to any ligaments or tendons in his arm. They scheduled for him to start Thursday. On Wednesday, Strasburg felt a sensation “like a strong cramp,” he said, as he warmed up.

Strasburg felt fine once he got loose, but the Nationals did not want to risk pitching him Thursday. Johnson said Strasburg wanted to pitch, but Johnson pushed him back.

“I think anybody that has ever had an arm injury is a little more cautious,” Johnson said. “And rightfully so. That’s true of anybody that’s ever had a problem, whether it’s a hip problem or a back problem. You know what it’s like when it starts coming on, and you know what it’s like to be disabled. It’s normal.”

Strasburg will likely make two more starts this season. Right now, he has made 28 – the same number he had last season, when the Nationals voluntarily shut him down. Strasburg has thrown 170 innings this season compared to 159 1/3 last year. Owing to his forearm ailment and a rain-shortened, two-inning start, Strasburg has thrown only 14 innings since Aug. 23.