He knows it. Jim McElwain knows it. And everyone else is beginning to count on him for success at wide receiver in the 2019 season for Central Michigan.

Sullivan's head was down, and he spoke quietly when talking with reporters after CMU's spring practice on April 13 – a sign of his humility, maturity and growth. However, he's as intense as anyone once the whistle blows.

Things are different around the football program. Sullivan is embracing the clean slate given by McElwain to all players in order to solidify himself as an offensive weapon.

So far, it's paying off.

"He's done a really good job," McElwain said of Sullivan. "I think he's really responded to the disciplined and really what it takes to be a great teammate.

"He's a guy that's going to be able to play all spots for us."

From the time McElwain conducted one-on-one interviews with each student-athlete in early December, the first-year coach gave the Chippewas a fresh start, as if he had no prior knowledge of their abilities.

Sullivan might've been lower on the depth chart in recent seasons, but that's not the case anymore.

"Everyone had a chance to prove themselves," Sullivan said. "I feel like I have done well."

One of McElwain's early messages to the team was to attack each day. Sullivan said he took that to heart and continuously uses it for motivation to achieve greatness.

"We've been coming in hard, listening to what (McElwain) has to say and doing what we need to do," Sullivan said. "As you see in the long run, it all takes care of itself as we continue to work hard."

The 6-foot-1, 221-pound receiver came out of Muskegon High School ranked No. 29 on the Detroit News Blue Chip list and as an Associated Press Division 3 First Team All-State member. During his senior campaign, Sullivan started both ways.

Upon entering the college ranks, he played eight games in 2017 – all on special teams. He scored his first touchdown in CMU's 17-5 victory over FCS Maine on Sept. 22, 2018, but didn't begin showing signs of dominance until midway through the season.

Sullivan's top college game to date was when he went for 74 yards and one touchdown on four receptions against Buffalo on Oct. 6. He's observed growth from his position group since then and hopes each player increases his numbers from a season ago.

"There's been all around improvement from everybody – every skill position," Sullivan said. "We've all been putting in work."

"We all got a lot of stuff to work on."

Senior Brandon Childress, who made a number of impressive catches at open practice, is a veteran in the wide receiver room with Sullivan. Childress sustained an injury in 2017 doing a touchdown dance and, one year later, made just 15 catches for 155 yards without a touchdown in seven games.

McElwain said Childress has grown up in a variety of ways, just like most of the receivers.

"We've had a lot of guys in this program that started realizing it's not about them, but it's about their teammates and what they can do to help the Chippewas be good and win a championship," McElwain said. "A couple of those troubled position groups have really grown up, and it's great to see that."

Sullivan and Childress also face an interesting situation in terms of the quarterback battle. The starter is unknown, and a few fresh faces are in the mix for the job.

However, Sullivan said he doesn't care who takes the field as the signal caller, but he spoke highly of Houston graduate transfer Quinten Dormady.

"Quinten does a good job as a leader," Sullivan said. "He knows where everyone needs to be for the routes. If I don't know something, he'll be the first one to tell me what route to run. He does a good job of throwing. He has a strong arm, pretty accurate."

Dormady began the 2017 season as Tennessee's starter before a shoulder injury that required surgery stopped his season short. He went to Houston for 2018 but never fully recovered, resulting in a rare double graduate transfer. Through 14 college football games, the 6-foot-4, 222-pound quarterback completed 102-of-181 passes for 1,290 yards, seven touchdowns and six interceptions.

Getting back on the field in spring for fans to watch is normal for most players in college football. It's just another opportunity to showcase skills and display newfound talent.

Not in Sullivan's case.

For the wide receiver from Muskegon, it was personal after an atrocious 1-11 season in 2018.

"To come back out here on a new start and journey, it felt good," Sullivan said.