Johnson (6-2, 293), along with over 20 other rookies, will report to Valley Ranch on Thursday for the Cowboys first mini-camp.
"I was really down most of the day because I really thought I would go in the later rounds," Johnson told GoBlueRaiders.com. "When I finally heard the phone ring, my heart was pounding and I almost lost my breath. It was exciting and I can't wait to get started and prove myself."
Johnson recorded 47 tackles, including 8.5 for loss and four sacks last season for the Blue Raiders.
Cowboys Sign Thomas Johnson
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