Jackson pitched at Calvary Christian Academy in Fort Lauderdale, Fla., where he was 8-1 with a 0.90 ERA while leading his high school to the Florida Class 2A Regional Quarterfinals. The Rangers worked hard at signing Jackson, who had a scholarship waiting for him at the University of Miami in case the Rangers missed Monday's deadline.
Grimm, considered a power pitcher with a fastball in the range of 90-96 mph and a sharp curveball according to Baseball America, was 3-7 with a 5.49 ERA his senior season with the Bulldogs after missing most of his junior year with a broken arm.
Both Grimm and Jackson will report to the Rangers' Rookie League affiliate in Arizona.
Chris Girandola is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.