Marcus immediately saw the difference between the players' attitude in high school compared to college ball.
"Back in high school you lingered around, hanging with your buddies more. When you get to college it's more serious, kind of like a job type of thing," noted Marcus, who turned down scholarship offers from New Mexico, Iowa State and Air Force to sign with Mississippi State. "They are throwing everything at us right now and I'm trying to keep up. I'm just trying to learn the defense, learning what (my) job is, (my) assignments, how to line up."
But he's quickly adjusting with hard work not only on the field, but in the meeting rooms.
"Once you read your playbook, be in meetings all the time and talk about it, get more reps, you get more comfortable on the field," said the youngster.
The intensity on the field is another aspect that quickly taught him the seriousness of college football.
"It seems like every play is intense, everyone gives 100% every play," said Marcus. "And they are bigger and stronger, but I use my speed to keep up with them. God blessed me with some speed, so I just try to use that."
But Marcus matches that intensity with an intensity not normally seen from a true freshman.
"I always try to give 100% every play, never quit on a play," he said. "I take a lot of pride in everything that I do. I never want my man to score. That's my objective, never let them score, never let them outrun me."
During the first scrimmage, he showed that never-quit attitude.
"I almost gave up a big play, but I went down and chased him down," said Marcus, who chased down Tyler Threadgill, considered the fastest player on the team. "I never quit on the play."
As of now, his effort and athletic ability has him moving up the depth chart.
"On the base defense, I'm the third-string. But I'm second-string on different nickel packages," he said.
And as he continues his steady improvement, don't be surprised if he moves even higher up the depth chart over the course of the season.
Gene Swindoll is the publisher of the Dawgs' Bite, Powered by GenesPage.com website, the source for Mississippi State sports on Scout.com sports network. You can contact him by emailing firstname.lastname@example.org.