As fun as it is to watch, it's also concerning. The Hawkeyes are thin at the position. An injury to Coker might prove very costly.
Adam Robinson took a shot against Michigan State last season that caused a concussion. The then Iowa starter never recovered before off-field issues eventually ended up costing him a spot on the roster.
Coker lowered his body onto an unfortunate Northwestern Defensive back a few times Saturday night. There was no question who got the worst of the collision.
It's a fine line when playing football. Playing scared could result in an injury. It's an instinctual sports, especially for a ball carrier.
Iowa Coach Kirk Ferentz doesn't mind seeing his 6-foot, 230-pound running back dish out some punishment.
"Marcus is a strong runner, and you know, I can't imagine it's a lot of fun tackling him," Ferentz said. "It's been 35 years since I've played, but you know, to me I think he's got to make that an advantage. And that's football."
Coker said that he just tries to keep his pads low so he can deliver more punch than he receives in those situations. He doesn't worry about his head being down with the pads and the possibility of an injury there.
'When I think too much, is when I have trouble," Coker said. "I just try to think as little as possible."
The battle in his brain contributed to some early fumble issues this season and them some over-cautious running from the true sophomore. He explains what it's like in his head during those times.
"It's crazy," he said. "You thinking one thing and then it hops to another and it hops to another. It's all in a split second and just jumbled up."
Coker has received all but three carries the last two games, giving way to DeAndre Johnson in the closing minutes against Northwestern. He's toted the ball 127 times through six games for 578 yards and six touchdowns.
"The more reps, the more comfortable I am," Coker said.
Iowa plays Indiana this Saturday in a Homecoming game at Kinnick Stadium. Coker will face the opponent against which he started his first college contest a year ago in Bloomington.
"It was exciting," he said. "I was really nervous before the game. That was the most nervous I've ever been before a game."
Coker said the nervousness never left during the game against the Hoosiers. It didn't seem to matter has he rumbled for 129 yards on 22 carries in a 18-13 Iowa win.
It was the first real look Iowa fans had of the Coker style.
"If you break the line, which he did a couple of times the other day, there's always going to be somebody lurking back there and if you're a strong guy, run strong," Ferentz said. "If you're Ronnie Harmon, make one move and make the guy look like a fool but there are not many Ronnie Harmons. In fact, there's been one that I've seen in a long time.
"To me, just have to play through what you play and backs are going to get tackled. That's the nature of the game."
Ferentz said Coker looked a lot more decisive than he had in recent games in gaining 124 yards on 22 carries and two scores against Northwestern. The coach said that hasn't always been the case with his young back, agreeing that the Maryland native might over think things at times.
"Defenses close too quick, so you really kind of have to make a decision at some point, hopefully sooner than later," Ferentz said. "If it's wrong, it's wrong, you have to live with it and go. You know, it's kind of like making a call sometimes.
"So you just have to do it, and live with it instead of trying to be perfect all the time and I think that's kind of what I was sensing a couple of weeks running."
Iowa opened the season thinking true freshman Mika'il McCall would help ease Coker's workload. The Chicago native broke his leg in the season opener.
Ferentz said on Tuesday that McCall's return this season was up in the air.
"I look at he and Nolan MacMillan, they could come back; they might not, too," the coach said. "So I think that we just have to take the mental approach that they are not with us, and if they make it back, it's a bonus. On a couple of levels it's good for development and I think it's the same way with these two guys. Hopefully they will it get back at some point."
Another true freshman, Jordan Canzeri, who gave up his redshirt in Week 4, didn't play the following game a Penn State and missed the Northwestern game after injuring his hamstring last Tuesday in practice.
"I don't know if he could have played or not last week," Ferentz said. "He probably could have played Saturday as well, but he didn't practice all week, so kind of threw a monkey wrench in that one. As I understand it he'll be ready to go this week."
Johnson carried three times for 18 yards in mop-up duty against Northwestern. He has rushed 11 times this season making him the only back other than Coker to reach double-digits in totes. True freshman Damon Bullock and junior Jason White also have seen limited duty in the backfield.
There's a chance Canzeri or someone else could step up and prove to the coaches that he can lessen Coker's load. But for now, Big Ten secondaries should be on the lookout for a runaway bulldozer coming their way.