Roby was a three-year starter for the Buckeyes.
He has eight career interceptions and 36 pass deflections.
He had 69 tackles and three interceptions and two blocked punts last season and was named All-Big Ten Conference.
Seastrunk is an Oregon transfer who rushed for 1,177 yards and 11 touchdowns last season.
As a junior, he rushed for 1,012 yards and eight touchdowns.
Shazier had 101 tackles, 22.5 for losses last season for the Buckeyes.
Shazier had a 42-inch vertical leap, 10-10 broad jump and bench pressed 225 pounds 25 times at the NFL scouting combine.
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Aaron Wilson covers the Ravens for The Baltimore Sun