(Renton, WA) -- The Seattle Seahawks' fourth-round draft pick is officially part of the team's roster after signing his rookie contract. Defensive end Cassius Marsh, who was chosen 108th overall, recorded 60 tackles and six sacks last season for UCLA. Seattle has now signed four of its nine draft picks. The Seahawks also have announced deals with Southern University tight end Rashaun Allen and guard Nate Isles of North Carolina A&T, both undrafted free agents.