He’s the only Kansas football coach ever tendered a “lifetime” contract. During his tenure (1958-66), Memorial Stadium was expanded twice.

And he recruited Gale Sayers, arguably the most famous KU football player of all time.

Yet Jack Mitchell left college football coaching at the relatively young age of 43 — current KU coach Mark Mangino was 46 when hired in 2002 — and never looked back.

Mitchell was a helluva recruiter. He was a gregarious, back-slapping, cigar-smoking extrovert who was probably a better businessman than he was a coach.

Mitchell always blamed his firing following back-to-back dismal seasons in 1965 (2-8) and 1966 (2-7-1) on the distractions of buying into a Lawrence bank and a Topeka insurance company as well as the purchase of a newspaper, the Wellington Daily News.

“I got so involved in those things,” he told me several years ago, “that I did a terrible job of coaching.”

As difficult as it is to believe today with Mangino making more than a million dollars a year, Mitchell actually banked more money from his business connections than he did from coaching.

“I paid more in income taxes on my business involvement than I was making at KU,” he told me.

He was one of the highest-salaried football coaches in the country at that time, too. When he was fired, Mitchell was making $20,300 a year. With inflation, that number would be well into six figures today, but not close to $1 million.

Of course, that was long before television contracts blew the door off the safe and before university constituencies grudgingly accepted a coach earning more money — in most cases much more money — than a dean.

No football coach in KU annals has ever commanded the “lifetime” deal Mitchell received in 1961. It really wasn’t a lifetime pact, though. Specifically, it was for 10 years.

However, the contract included an unusual clause stipulating Mitchell must receive at least two years notice of termination and, if he didn’t, he automatically received a three-year contract extension.

As sweetheart a deal as that was, it nevertheless contained another clause you won’t find in a contemporary college football coach’s contract. It was a clause that prevented Mitchell from earning an annual salary exceeding the average of the salaries of the university deans.

So what happened when Mitchell was fired with five years remaining on his “lifetime” contract?

Mitchell did not receive the $100,000-plus he was owed. KU paid him in full for the sixth year, but Mitchell settled for $56,000 that was paid off at the rate of $14,000 a year for the next four years.

Mitchell’s nine-year stint came to symbolize what was to become a common perception of KU football. The highs were exhilarating, but the lows were dreadful. (You don’t want to know, for example, about the stultifying 3-3 tie with Kansas State in 1966).

Colleague Bill Mayer, one of the few writers still around who covered KU football back in those days, delights in telling Mitchell stories.

On the record, Mitchell usually resorted to coach-speak, particularly after a win but take a mic or camera out of his face and, as Mayer once wrote, “Boy, could he spellbind quarterback clubs when he got them face-to-face.”