His first impression when he arrived at the headquarters of the Super Bowl champions?
"I think when it kind of hit me when I was rolling up on the facilities here. I've never seen anything so beautiful in my life," Marsh said.
"The lake; we practice next to a lake. That's unbelievable. The facility looks like its own little city. It's just ridiculous to me. I love it here."
Marsh is trying to leave as strong an impression as possible during the three-day rookie camp because he has to return to school. The next time he'll be back with the Seahawks is sometime in June and before full squad minicamp.
But he'll be headed back to school with a playbook and a plan to start adding weight to his 254-pound frame.
"They just want me to come in here and compete," Marsh said. "They know that I'm a versatile player and I can play a multitude of positions defensive end, rush from a three (technique), play outside, play all over the place and I think that's what they expect from me to just come in here and compete wherever I can. I don't think there are any predictions or anything."
Marsh was the first of Seattle's three fourth-round picks (along with wide receiver Kevin Norwood and linebacker Kevin Pierre-Louis) in last week's NFL draft. He was taken by the Seahawks because he fits the profile of the defensive linemen that have proven successful for their system: lean and quick with long arms and the versatility to play up and down the line.
Seattle believes Marsh can be a lineman in the style of Michael Bennett with the ability to hold the edge as a defensive end, but also provide an interior pass rush lining up as a defensive tackle.
Marsh knows the subtleties of all the defensive line positions. When he arrived at UCLA he was 300 pounds and playing defensive tackle. As he got into better shape and dropped weight, he moved outside and played defensive end for the Bruins.
But Marsh knows he can't play at that weight in the NFL. There is no set deadline for when he'd like to add a few pounds to his frame. Marsh wants the additional bulk to come naturally as he gets more into the Seahawks system.
"I'm just going to continue to work hard. I do need to gain weight, but I'm going to do it the right way and get with the nutritionist and the weight coach and work extremely hard and do the things I need to do," Marsh said.
One skill that has stood out to Seattle's coaches already is Marsh's hands. He said some of that is natural, but he also did mixed martial arts training in college that has increased his hand speed and strength.
"He's a real natural pass rusher. He has great stuff already," Seattle coach Pete Carroll said. "You can see he has really good hands and has a good feel for it. What will be important as we move on is to figure out where he could best fit in. We'll be real open to seeing that."