Bryce Harper, the No. 1 pick in the 2010 draft, will play for the Nationals in the Arizona Fall League, a team official confirmed.
Harper, who turns 18 on Saturday, will get a chance to test himself against some of the game's top prospects after hitting .319 in the Nationals' instructional league in Viera, Fla.
The outfielder flashed both his inexperience and his prodigious power in the league, leading the team in RBI and runs scored and blasting a handful of opposite-field homers.
The Nationals signed Harper minutes before the Aug. 16 deadline to sign draft picks, and at that point, a source close to Harper said it was likely the team would send him to Arizona. But the Nationals wanted to see how he'd handle his first taste of pro ball in the instructional league before making a final decision.
Update (1:27 p.m.): MASNSports.com's Byron Kerr just spoke to Harper, who said he will head to Arizona on Sunday after taking the weekend to celebrate his 18th birthday with his family in Las Vegas. Both Byron and I will have more this afternoon.