While he's in the majors, he'll not use up rookie eligibility this season.
This article, with a fantasy emphasis, projects him as one of the prospects to possibly grab now for help down the line in keeper / fantasy:
Brad Peacock, Nationals
I covered Peacock in a Mining the Minors column from last month. The right-hander has come a long way in 2011, to the point where he’s now seen as a potential mid-rotation starter. His first start in the majors was very solid — 5 IPs, 2 hits, no runs, 3 walks and 2 strikeouts against the Mets — and he’ll get another outing or two so the Nats can gauge just how soon he’ll fit into their 2012 plans. After posting a 2.39 ERA, 0.99 WHIP and 10.9 K/9 over Double- and Triple-A, the guess here is he begins the season back in Syracuse for a month or two before getting his shot. Then again, Washington’s rotation is in flux outside of Stephen Strasburg, Jordan Zimmermann and John Lannan, so a good spring could hasten Peacock’s timeframe. The upside here, though, isn’t quite as big as the names ahead of him, so Peacock is more of a streaming option in NL leagues, with the possibility of becoming a spot-starter once we see how he performs early on.
