MIAMI — The Nationals shut down their top pitching prospect for the remainder of the season Monday. Their history with similar shutdowns is best described as “much-discussed.” But the decision to shut down right-hander Erick Fedde hardly warrants any discussion at all.

The 24-year-old right-hander has a right forearm strain, the kind of injury he might need a week or so to rehab during the season, but will not test in September. Because of the shutdown, the 24-year-old will throw fewer innings this season than last, which is not generally the preferred progression. Normally, the Nationals increase a young pitcher’s workload from season to season.

But while Fedde’s injury likely would allow him a few relief appearances at the end of the season if all went well, the Nationals made the somewhat obvious decision to protect  one of their few remaining young pitching assets. They already lost Joe Ross to Tommy John surgery just after the all-star break, a procedure that will take him out of the running for the fifth spot in their rotation next season. Despite his 9.39 ERA in three major league starts, Fedde will almost certainly be in the running for that spot if he is healthy in February.

“He’s a guy we’re going to be counting on to be in the rotation for next year and beyond,” Nationals General Manager Mike Rizzo said. “He’s probably the next wave of guys we’ll be talking about.”

Without Ross, and because A.J. Cole has never really seized a spot in the Nationals’ rotation, Fedde might be the most likely internal candidate to be their fifth starter out of spring training next season. They could, of course, choose to bring back Edwin Jackson or find starting depth via trade or free agency. But if their starting arsenal stays as it is now, Fedde could begin the season as an everyday starter, despite the fact that he had never pitched above Class AA before this season. Fedde pitched to a 3.69 ERA in 29 appearances (13 starts) in Class AA and Class AAA this season, struck out 79 batters in 90 1/3 minor league innings and held opponents to a .239 batting average.

“I think [this season] was beneficial to him because he tasted the big leagues, tasted Triple-A for the first time. As we controlled his innings, he got a taste of pitching out of the bullpen and starting in the big leagues,” Rizzo said. “So I think it’s going to be beneficial for his development, and I think it’s going to give him a giant step forward coming to spring training next year.”

Rizzo has a history of adding starting pitching depth, even to the deepest of staffs, and will enter this offseason with less depth than usual. Consequently, while his top four starters are under contract for next season, the Nationals seem likely to explore the market — if not shop aggressively. Entering the season with Fedde as the fifth starter qualifies as a risk, not so much because of the forearm injury, which Rizzo seems to think is relatively minor, but because he was not consistent enough to find major league success and has not pitched anything near a full major league season’s worth of innings. The most starts he has made in a professional season is 24.

But if the Nationals decide they can absorb the risk of his stamina, the question of his stuff seems like less of a concern. In his last major league start, Fedde showcased a curveball he didn’t have in spring training, honed this season at Mike Maddux’s suggestion and was throwing for strikes within a month. He threw his change-up more than he did last season in the minors. He tinkered with turning his slider into more of a cutter, or perhaps using both.

“He learned a lot of different things, and kind of learned them at an advanced level in Triple-A and in the big leagues,” Rizzo said. “I think he’s going to be better for it. He’s added to his repertoire.”

The repertoire with which he started the season — mainly fastball, slider and the promise of a change-up — earned him spots on all the top 100 prospect lists before this season. Assuming his velocity returns when his forearm heals, that arsenal will grow, now including a curveball and better change-up that look nearly ready.

Fedde allowed 33 base runners in 15 major league innings this season. He struck out 15 batters and walked eight. To choose Fedde as their fifth starter out of spring training (or later), the Nationals must be confident those ratios will improve. They also must be confident he is healthy, which is why the rookie’s first season of major league action ended Monday, with more than a month left in the regular season.

MAGIC NUMBER:10

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