A private family memorial will be held at a later date.
Pisarski Funeral Homes of Stevens Point & Plover assisted with arrangements.
Condolences may be offered online at www.pisarskifuneralhome.com.
Mr. Diehl was the son of the late William and Ann (Katzer) Diehl. He graduated from Messmer High School in Milwaukee in 1948. He was an all-conference selection on both the football and basketball teams his senior year, when each team won a state championship.
He attended Marquette University on an athletic scholarship.
He was married to Carol Bartl on Feb. 16, 1963, at St. Pius Catholic Church in Milwaukee.
After being discharged from the service, he took a job with Sentry Insurance, where he worked for 33 years.
He promoted Catholic education for many years as a member of the Stevens Point Area Catholic School Board. He was a member of St. Joseph Catholic Church.
Survivors include his wife; one son, Bill (Kelly), Minneapolis, Minn.; one daughter, Chris (Sal) Ripoli, Fountain Hills, Ariz.; and two grandchildren.
He was also preceded in death by one sister, Judy Kelly.