Both players have faced legal woes since the conclusion of the 2009 season.
Blatnick was charged with felony assault and battery with a dangerous weapon after a brawl with former teammate Stephen Denning. Johnson is facing a charge of marijuana possession and a DUI allegation.
The school has not announced whether or not Blatnick and Johnson will be suspended.
OSU will have its first practice in shoulder pads on Sunday and its first full-pads practice on Tuesday.
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