The Rays signed Taylor Guerrieri, according to Marc Topkin of the St. Petersburg Times (on Twitter). The sides agreed to a $1.6MM deal, according to Jon Heyman of SI.com (on Twitter). The Rays selected the right-hander 24th overall in June. Guerrieri had a scholarship offer at South Carolina, but decided instead to sign with the Rays, who had ten of the top 60 picks in the draft.
You can keep track of which top picks have signed with MLBTR's list.