One of the assistant coaches who helped legendary coach LaVell Edwards turn BYU into a nationally prominent college football program in the 1980s and 1990s has died.

Former BYU offensive coordinator and offensive line coach Roger French, who spent 21 years coaching at the school in Provo, died in Minnesota from causes incident to age Saturday morning. He was 86.

Roselyn Daley, a former secretary in the BYU football offices, confirmed French’s passing on Facebook. French’s wife, Dottie, died last year. He was living in an assisted living home near his house in Maple Grove, Minn.

Edwards died in late December of 2016. He often credited French for his help in revolutionizing the passing game in college football.

“Roger French was a great coach and a great person,” BYU football coach Kalani Sitake said on Twitter. “It was an honor to have him as a coach and a mentor.”

French produced several all-American linemen at BYU and also mentored Kansas City Chiefs coach Andy Reid, a Cougar lineman in the 1970s.

“My heart hurts,” former BYU offensive lineman Hans Olsen wrote on Twitter. “For all those [who] knew BYU O-line coach Roger French, you’re better for it. … He was a huge part of the success that LaVell had and was a positive influence for so many.”

French graduated from the University of Minnesota in 1956 and was a Minnesota High School Hall of Fame inductee in 2010. But he did his best and most notable work in Utah, where he became a member of the BYU Athletics Hall of Fame.

At BYU, French coached the likes of Outland Trophy winner Mo Elewonibi, Bart Oates, John Tait, Trevor Matich and Evan Pilgrim.

French was on the staff that coached BYU to the 1984 national championship and was a co-offensive coordinator with Norm Chow. Offensive lineman who were coached by French were often called “French’s Legion,” and more than 40 went on to play professional football.

BYU offensive coordinator Robert Anae and offensive line coach Garett Tujague traveled to French’s home in Minnesota in the summer of 2014 and found boxes of VHS tapes and binders filled with offensive plays and coaching instruction that French had saved in his garage.

“He knows more about offensive line play than any man I know,” Tujague said after the trip.

Reid once called French “The Creature” in a column he wrote for a Provo newspaper, due to French’s eccentric nature and his habit of sleeping at his office in the Smith Fieldhouse during the season so he could work around the clock.

Funeral plans will be finalized Monday, according to Gail Luedke, French’s daughter.