Fry, 82, a veteran of nearly four decades as a collegiate head coach (SMU, North Texas State, Iowa), has had some clunkers over the years. He’s faced criticism. He has some advice to help Diaco, 37, deal with the scrutiny he's had lately.
"I didn't pay any attention (to the criticism) and I instructed my assistants to do the same," Fry said. "There are a lot of people out there evaluating and most of them have never had a jockstrap on in their life.
"How do you handle a game (like Navy)? Real simple. Forget about it. You can't change anything. Take away the lessons you learned and forget about the game. It's over."
Fry has walked in Irish head coach Brian Kelly's shoes. At all three of his stops, he took over struggling programs and within three years had won championships. He sees similarities at Notre Dame.
"From a psychological standpoint, I had it easy," Fry said. "I inherited a group of players that had just had its tail kicked. A loser is the easiest group in the world to motivate.
"If you check the past few seasons at Notre Dame, they weren't all that good. That's why the previous staff isn't there. I think everybody has to be a little patient; give (the Irish coaches) time to put everything in. It's a new learning cycle for the players. It takes time."
Chronologically, time isn't a factor for Fry. There's an argument that Diaco's too young for such a high-profile job.
"Frankly, in my opinion, age has nothing to do with it," Fry said. "I know a lot of old coaches who have experienced tragic games."
Fry has his own unique, country-fied definition of a leader - and Diaco was one of his best.
"I was raised on a farm," Fry said. "My father taught me a lot of great lessons. He'd take me behind the barn, grab the horsewhip and tell me to bend over.
"He'd say, 'I want you to remember this the rest of your life.' He'd tell me to bend over and he'd say, 'I want you to remember this the rest of your life.' I said, 'Daddy, what is it you want me to remember?' He said, 'I want you to fill the pickup truck with hay and feed the cows."
Fry said his family farmed, but didn't own, between 1,500 and 2,000 acres. How was he going to find the cows in that expanse?
"My daddy said, 'Drive the pickup out in the middle and wait a while. Pretty soon, you'll hear a bell ringing. That's the bell cow. Find the bell cow and you'll find the whole herd.'
"I used that lesson as a coach. I observed all the positions on the team. It doesn't take long to figure out who the bell cow is at each position. That's the guy you go to and say, 'This is the way you win. This is the way you lose. These guys will listen to you. You can help me.'
"That's the way you find a leader. That's the way you develop them. The bell cow is the whole secret. Bobby Diaco was my bell cow."
The Irish defense could use a leader right now.