WATCH: Patterson, McCaffrey, Kemp, Hudson & McKeon after Michigan Spring Game

Jim Harbaugh has handed the keys to Michigan's new-look offense to Josh Gattis , who is implementing a no-huddle, spread scheme.

How different is it?

"It's night and day," quarterback Shea Patterson said Saturday after the Wolverines practiced in front of fans at Michigan Stadium. "As far as the similarities, I think there are very few of them."

Patterson usually called plays from the huddle last season and regularly went under center for snaps in formations with multiple tight ends, a running back and fullback.

That will not happen much, if at all, this year.

Harbaugh used to be very much a part of what he described as a collaborative effort to call plays along with assistants such as former passing game coordinator Pep Hamilton .

Now, Gattis is calling the shots.

"It's easier for everyone," Patterson said. "You got a clear-cut guy in coach Gattis. Last year, so many other coaches had their hand in it and their input. (Gattis is) running things. It's obviously coach Harbaugh's team, but Gattis is totally running the offense."

Looking to shake up a stagnant offense, Harbaugh hired Gattis away from Alabama to be his offensive coordinator after not having an assistant with that title last season.

"Coach moved aggressively," Gattis recalled earlier this spring. "It came out of left field. He previously tried to hire me a few years back."

Harbaugh has had his eye on Gattis for years, hearing good things about a man who quickly climbed up the coaching ranks from Western Michigan to Vanderbilt to Penn State before Nick Saban added him to his staff with the Crimson Tide.

After working with Gattis on a day to day basis, Harbaugh has gotten even more fired up about the hire.

"Brings a lot of energy to meetings, the practice field," Harbaugh said earlier this month. "He's coaching a lot of people every play so I think that's been a good thing for all of our coaches."

Gattis is the play-caller, but he has plenty of help.

Between each shotgun snap, players look at the sideline to know what play is being called. Members of the football program's support staff hold up a number of signs with visual clues such as a lightning bolt or a train. Former offensive lineman Grant Newsome, who had a career-ending knee injury, stands next to Gattis on the sideline and signals the plays he calls.

"We have the tallest signaler in the country," tight end Sean McKeon said. "He's definitely easy to spot on the sideline."

Patterson is given a lot of power in the offense, which features a lot of plays that give him a run or pass option. He pitched the ball to running backs at times and also tucked the ball high and tight and kept it during the public practice. He also dropped back for some throws and had some play-action passes.

"Half those throws were RPOs that we could've ran or throw," McKeon said. "It gives Shea options. We're never in a bad look with an RPO. They stop the run or they try to blitz, then the throw is open. If they try to cover the throw, then the run is open. That's the biggest difference."

In the end, though, results will matter most at Michigan.

Harbaugh won 10 games last year for the third time in his four seasons with the Wolverines, but he fell to 0-4 against Ohio State and dropped a third consecutive bowl game.

"That one against Ohio State was unacceptable," Patterson said, adding the setback played a part in him returning for his senior season instead of entering the NFL draft.

The Buckeyes beat Michigan 62-39 for the seventh straight year and the 14th time in 15 years. Florida finished off the Wolverines, routing them 41-15 in the Peach Bowl.

"That's definitely lit a fire under some guys," McKeon said.