Edwards is a guard out of Tennessee State. Herron is a receiver who played his college ball at Wyoming. The signings were announced Friday, the first day of a weekend rookie minicamp.
Financial terms of the four-year agreements were not disclosed.
The Bucs used their entire draft on offensive players for the first time in franchise history. The team also selected receiver Mike Evans, tight end Austin Seferian-Jenkins, running back Charles Sims and tackle Kevin Pamphile.
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