A native of San Diego, Calif., Griffin was actually drafted higher than his 25-year-old brother, who's posted a 12-5 record and 3.35 ERA over the past two years for Oakland after being selected in the 13th round of the 2010 Draft.
"He was the Friday starter at LMU, has had a good college career. Likely a starter early in his career in the Minor Leagues, and then we'll see what happens from there," Rays scouting director R.J. Harrison said. "He's a tall, rangy guy that creates a pretty tough angle on right-handed hitters."
Griffin increased his strikeout totals in each season at Loyola Marymount, from 37 as a freshman to 72 in 88 innings as a senior. He also held opponents to a paltry .239 average in his final college season while walking only 19 batters all year.
Griffin was used exclusively as a starter this spring after pitching mostly in relief in his first three college seasons.
Adam Berry is a reporter for MLB.com. Follow him on Twitter at @adamdberry. This story was not subject to the approval of Major League Baseball or its clubs.