The biggest difference in Michigan State's offense now from a year ago will not be apparent to the naked eye when the team opens spring drills March 26.

Spartans' co-offensive coordinator Dave Warner said it's an attitude — not a scheme or a major personnel change.

"The biggest difference in our offense is our feeling as an offensive staff toward what we're going to be able to accomplish,'' said Warner, who helped direct Michigan State to a 13-1 record and a 24-20 Rose Bowl victory over Stanford in his first season as a play caller for head coach Mark Dantonio.

"There's a high level of confidence for us offensively, not just coaches, but our offensive football team,'' he said. "Our guys feel good about where they are at, but by no means do we feel we've arrived.

"There were so many questions at this time last year at various positions, and a lot of uncertainly.''

There will be some holes to fill next season.

Michigan State lost starting offensive linemen Dan France, Blake Treadwell and Fou Fonoti along with receiver Bennie Fowler.

Michael Dennis, an offensive tackle who also lined up at tight end last season, has also decided not to return to the team for his final year of eligibility. He will graduate in May, according to MSU associate athletics director John Lewandowski.

Warner said he feels comfortable the Spartans can sustain the losses of those players without having to make too many adjustments to the scheme.

This spring will be more about fine-tuning than overhauling, as was the case a year ago.

"I think you're always working to grow, you're looking for ways to expand, and we felt we had to do those things last year,'' Warner said. "We felt we needed to shake things up last year.

"But every year at this time is when you're investigating new ideas and ways to get the ball in certain guys' hands.''

Warner, who doubles as running backs coach, said he's looking at "quality control" things at his position.

"We ran the ball well last season,'' Warner said. "But our pass blocking at running back was not what it needed to be.''

Prior to being moved to running backs coach last season — a move that coincided with the promotion to co-offensive coordinator — Warner coached the quarterbacks. He continues to work closely with new QB coach Brad Salem at that position, and Warner has an idea where the fixes need to be made.

"At the quarterback position we got away with some mistakes, where we threw the ball into coverage and the ball wasn't intercepted,'' Warner said. "You forget about those when you end up winning the game.

"At the wide receiver position, we still can be a little bit better versus man coverage. I think that's the exciting thing about 2014, we have a lot of the pieces coming back.''