Seahawks third round picks
Seahawks draft guard Christian Haynes with 78th overall pick
Haynes lacks great height - he is only 6'2" - or otherwise he would likely be a much higher pick. He has the agility and strength to play in the NFL and weighs 320 pounds so he won't need to gain much more, if any. Technically, Haynes is already ready for the next level as he takes excellent angles and anticipates what a defensive player is going to try to do against him.
Even though Haynes did not play at a Big 5 school, Connecticut still played a decent schedule with games against Tennessee, Maryland, and Duke. I bring that up because Haynes allowed just one sack this year and only 3 sacks in the last three seasons. He also allowed just 4 total quarterback hits in three years. Seattle might need to replace left guard Damien Lewis and Haynes could step in sooner than later to do so.
Seattle drafts defensive lineman Ruke Orhorhoro with 81st overall pick
The Clemson product has good size at 6'4" and 290 pounds. Plus, the Seahawks certainly need defensive line help as Leonard Williams is likely to leave in free agency and so could Mario Edwards, Jr. Orhohoro isn't quite ready to take up all the reps lost by Williams or Edwards, but he has the raw skills to develop into a player who could.
The biggest issue for Orhorhoro immediately is that he has to develop better pass-rush moves. He only seemed to learn how to bluu-rush. He has good strength, but not enough strength yet to battle NFL offensive linemen. The guess is that Macdonald will know how to get him ready and productive earlier than most coaches.