The Draft concludes on Saturday, with exclusive coverage of Rounds 11-40 beginning on MLB.com at 1 p.m. ET.
The 6-foot-1 shortstop was named the Sunset League Player of the Year after hitting .396 with seven home runs and 22 RBIs. Schales showed patience at the plate, striking out just eight times and earning 21 walks in 114 appearances.
The Marlins see a hitting approach similar to Rays' third baseman Evan Longoria -- which is fitting because Schales is committed to Longoria's alma mater, Long Beach State.
"He has a real fundamental knack to hit. A quiet, calm player," said Stan Meek, the Marlins' vice president of scouting. "I hope he's not the next Longoria in terms of being a college player, but a high school Longoria that signs."
Maria Torres is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.