Receiver, linebacker will leave Iowa St.
Rhoads announced the moves Friday.
Johnson, a native of from Troup, Texas, caught 16 passes for 102 yards as a junior last season. He had a promising freshman year, but he suffered an ankle injury on his first series in 2009 and caught just seven passes.
Hamlin, a redshirt sophomore from Jupiter, Fla., was buried on Iowa State's depth chart.
Copyright 2011 by The Associated Press
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