NEW YORK (Reuters) - Hard-throwing pitcher Gerrit Cole of UCLA was taken by the Pittsburgh Pirates as top pick of Major League Baseball's First-Year Player Draft Monday.

The draft of college and high school baseball prospects by the 30 MLB teams is conducted over three days.

"It's really a dream come true," Cole told MLB Network TV. "You want to play Major League Baseball. Every kid grows up dreaming about that."

The 6-foot-4, 225-pound (102 kg) Cole has been clocked throwing as fast as 102 mph and is able to maintain his velocity deep into games with an arsenal that also includes a slider and change-up.

With the second pick, the Seattle Mariners took University of Virginia left-hander Danny Hultzen, who registered an 11-3 record last season and was 31-5 in his three-year collegiate career.

The pitching-rich Mariners, whose young rotation has them contending this season in the AL West, have selected pitchers with their first pick in five of the past six drafts.

The Arizona Diamondbacks continued the pitching trend by taking another UCLA right-hander, Trevor Bauer, with the third pick of the first round.

With their second pick of the first round (seventh overall) the D-backs selected right-hander Archie Bradley of Broken Arrow (Oklahoma) High School.

The first position player taken was high school outfield prospect Bubba Starling, who was selected fifth overall by his hometown Kansas City Royals.

Starling may not ever suit up for the Royals organization. The strong-armed prospect has also been recruited to play quarterback for the University of Nebraska and has until Aug 15 to make his decision.

Money may become a factor in making his choice. Over the last five years, the fifth overall pick in the baseball draft has averaged a signing bonus of around $4 million and he may be offered more than that to lure him away from the gridiron.

The draft is key tool for teams to stock their minor league franchises but is far from an exact science as young players can take several years to hone their game before competing on major league diamonds.

Starting with the selection of Chipper Jones by the Atlanta Braves in 1990 through 2010 top pick Chris Sale of the Chicago White Sox, there are just 11 former number one overall picks playing in Major League Baseball.

(Writing by Larry Fine, Editing by Nick Mulvenney)