A year after taking similarly hyped right-hander Stephen Strasburg, the Nationals took Harper, who can play catcher but was announced as an outfielder at the draft site at MLB Network studios by commissioner Bud Selig.
"Frankly, I didn't think that it was that much of a surprise," Selig said while a few dozen fans cheered in the studio.
It wasn't, but where the Nationals plan to play him was.
Harper showed solid defensive instincts behind the plate and called pitches much of the time, but the Nationals think his bat could get to the majors faster if he plays outfield.
"I can get better out there, I think," Harper said. "Anywhere they need me, I'll play. I just want to make it and we'll see what happens when I get there."
Nationals general manager Mike Rizzo envisions Harper as a No. 3-type power hitter with a strong arm in right field.
"We're going to take the rigor and the pressures of learning the position, the difficult position of catcher, away from him," Rizzo said, "and really let him concentrate on the offensive part of the game and let his athleticism take over as an outfielder."
The 6-foot-3, 205-pound Harper surpassed former big league pitcher Alex Fernandez, who went fourth overall to the Chicago White Sox in 1990, as the highest-drafted JUCO player.
With the second overall pick, Pittsburgh selected hard-throwing Texas high school right-hander Jameson Taillon. He was considered by many as the top pitcher in the draft with a fastball in the mid- to upper-90s that overpowers hitters on a regular basis.
Baltimore went next and picked smooth-fielding Florida high school shortstop Manny Machado, who has drawn comparisons to Alex Rodriguez for his ability and background, and Cal State Fullerton shortstop Christian Colon went to Kansas City at No. 4. The spray hitter is tough to strike out, but not spectacular defensively and could end up at second base.
With the fifth pick, Cleveland took Ole Miss left-hander Drew Pomeranz, the Southeastern Conference pitcher of the year with the Justin Bieber haircut. The first college pitcher taken, the Rebels' career leader in strikeouts mixes a 90-94 mph fastball with a knee-buckling curve.
Harper is expected to seek a record contract through his adviser, Scott Boras, who last year negotiated a record-breaking four-year, $15.1 million deal with the Nationals for Strasburg. The top overall pick last June is scheduled to make his major league debut Tuesday, almost a year to the day after he was drafted.
"I can't remember where back-to-back years where there's two players that have separated themselves from the rest of the field the way Strasburg did in '09 and Harper does in '10," Rizzo said. "In that respect, it is very, very unique. I think it's a lucky time to have two No. 1 picks overall."
The Nationals have until Aug. 16 to sign Harper, who has said he has plenty of options, including going back to Southern Nevada for another year if negotiations go awry.
"He's a player that wants to get out and play," Rizzo said. "He's the type of guy that does not enjoy idle time."
Harper was the subject of a Sports Illustrated cover story while still in high school, and has reportedly hit balls over 550 feet. A hitter has not garnered that much national attention since possibly Florida State's J.D. Drew, who went No. 2 overall to Philadelphia in 1997 but didn't sign a contract.
Drew, also a Boras client, played in an independent league and signed the following year after he went fifth overall to St. Louis.
Texas A&M righty Barret Loux went sixth to Arizona, and North Carolina right-hander Matt Harvey was selected by the New York Mets at No. 7. Houston next took Georgia high school outfielder Delino DeShields Jr., son of the former big leaguer of the same name.
Florida high school righty Karsten Whitson went ninth to San Diego, and Texas-Arlington outfielder Michael Choice rounded out the top 10 picks by going to Oakland.
The draft's first- and supplemental rounds were to be completed Monday night, with rounds 2-50 selected over the next two days.