GLENDALE, Ariz. -- This August afternoon, 75-year old Tom Moore could be sitting on a chair in the sand at water's edge as gentle waves tickle his feet. He could be teeing off into a majestic fairway lined by live oaks draped with Spanish moss near his home in Hilton Head, S.C. He could be listening to the carefree giggles of his six step-great grandchildren. He could be living the good life.

But he is alone on the field in a silent, vast, air-conditioned stadium in the middle of a desert. He stares straight ahead. He is the first one to work, as he has been for virtually every assignment every day of his career.

When Moore was a boy, his father Howard told him to always leave early enough to be able to change a flat tire and still be on time. It became a way of life for Moore. (Dad, by the way, worked construction until he was 72 years old.) So it should not have been a surprise that Moore reported for his 50th training camp this year. Early, of course. And with great enthusiasm.

"I love being here, love doing this," he said. "I enjoy the process, the people associated with the process. They are my friends. They are the people I feel comfortable around. I enjoy working with players and seeing them have success. To me that's very rewarding."

Moore keeps thanking Bruce Arians for hiring him last year to be assistant head coach of the Cardinals. Profusely thanking him, every day thanking him, and going on about how he is forever indebted. He is grateful to work with a coach he relates well to. He also is grateful because four years ago, Moore thought the clock had hit zero on his football life.

His knees hurt so damn bad. It was a struggle to get through a practice, and his energy was depleted. He was using a cane to get around the facility he worked at for 13 years. He didn't belong on a football field, so the Colts quietly let his contract expire after the 2010 season. In spring of 2011, Duke coach David Cutcliffe asked Moore to come to Durham, N.C., to watch Peyton Manning throw in his comeback attempt. When Cutcliffe saw Moore's condition, he took him to an orthopedic doctor who recommended double knee replacement. Moore had one knee replaced in April, and the next in August. But he got more than new knees. He got a new lease on life. "It was like a miracle," he said. "All of a sudden you've got your quality of life back, your energy back, you are ambitious."

Moore was 72 by then, and white hair and wrinkles didn't look good on his resume. So he sat out a year. Then Arians, at the age of 61, became one of the oldest first-time head coaches in history. He had also worked with Moore in Indianapolis and thought his former colleague was a perfect for his staff partly because Moore was "one of the best teachers I've ever been around," and partly because Arians needed a consigliere.

"Every night Tom and I usually share a cocktail," Arians said. "I bounce things off him. I respect his opinion so much. He has a feel for where the team is better than anyone -- when is the time to back off or turn it up. If I have a gut feeling on something, he's the one I can bounce it off of. He's the guy I can bitch to. You aren't supposed to bitch to assistants, but I can bitch to him."

Moore has seen it all. His first training camp as a coach was in 1961 at the University of Iowa. Paul Krause was on that team. Moore missed two camps in the early 1960s when he was serving in the Army, including a period as an officer in South Korea. His first pro training camp 1977 was in Latrobe, Penn., with Chuck Noll's Steelers. He shared his dorm room with another coach. There was no air conditioning. If he wanted to make a call, there was a pay phone at the end of the hall for everyone to share. 

Moore would win two Super Bowls with Noll's Steelers. He also would build the foundation of his coaching career. "Chuck Noll's definition of motivation was this," Moore said. "When you teach someone how to do something, and then they have success doing it that way, they are motivated. That's what football is about."

In their first meeting, former Steelers wide receiver Lynn Swann helped Moore develop his coaching style. Swann told Moore the Steelers receivers didn't need to be taught how to catch -- they needed to be coached on what they weren't doing well. So Moore concentrated on reading coverages and adjusting routes. It was a similar approach Moore used with Manning years later. Every offseason, Manning and Moore would identify what the quarterback had not done proficiently enough the previous year, and prioritize improving those areas. Manning believes Moore belongs in the Pro Football Hall of Fame. "He had a tremendous impact on me," Manning said. "I still use a lot of his coaching expressions and sayings."

Moore was the mastermind behind the great Manning offenses in Indianapolis, and the Colts won a Super Bowl in the 2006-2007 season. The head coach of that team was Tony Dungy. Moore recruited Dungy to play at Minnesota, convinced the Steelers to sign him as an undrafted free agent, coached him and then worked alongside him for the Steelers, Vikings and Colts. "He's one of my favorite people in football, no question," Dungy said. "He teaches players not only the right way to play the game, but also the right way to think."

I first met Moore in the early 90s when he was coaching Barry Sanders and Herman Moore in Detroit. Other coaches revered him even back then. "You have to meet this guy," they told me. An audience with Moore always has been special. He can tell tales about coaching Terry Bradshaw, Franco Harris, John Stallworth, Mike Webster, Cris Carter, Rich Gannon, Randall McDaniel, Herschel Walker, Marshall Faulk, Edgerrin James and Reggie Wayne. "He is like a football encyclopedia," Cardinals receiver Larry Fitzgerald said. "He is a wealth of knowledge. It's been a privilege to be around him. I learn something new from him every day. He'll say, 'Larry, try this. Marvin Harrison had success with this.'"

Age has enhanced the coach more than it has limited him. Moore may frequently reference his experiences, but he does not long for the way things used to be. "The old days were great," Moore said. "The game has always been great. Just like the 1936 Ford was a great car. Now it's 2014, and the 2014 Ford is better than the 1936 model. I think the same can be said about football. Time moves on."

He won't be giving a power point presentation, or programming a tablet. With a wink he said he believes there still is a place for a legal pad and a No. 2 pencil. That does not mean he is closed-minded. Moore will tell you learning never gets old. He is known for using five-dollar words around players and forcing them to look up definitions.

He also will tell you he is not resentful about never becoming a head coach despite being one of the NFL's most respected assistants of the past 36 years. He interviewed for two head coaching jobs, with the University of Minnesota in 1984, and with the Lions in 2006. "I have not been cheated," he said. "I've lived a dream. Lived a dream. Been blessed. And the worst sickness that can hurt people is jealousy. It wipes you out. I feel very fortunate I didn't have that sickness. I'm never going to be a head coach. I don't worry about it. My satisfaction is to help the coach I'm working for and help the players I'm coaching."

Arians marvels at the passion Moore had and still has for football. When Moore was a young coach and other coaches took vacation, he would traverse the country attending football camps. "Everybody has an addiction," Moore said. "My addiction is games. I tell people, I've never smoked that shit you guys smoke. I've never sniffed that shit you sniff. I've never shot that shit. But if it's any better than Sunday at 1 p.m., it's some powerful shit. Sunday afternoon at 1 p.m., that's fantastic."

Moore won't give it up, can't give it up. Not now, not for as far ahead as he can see. "As long as I got my health and my energy, I'm going to go until nobody will hire me," Moore said. "The term retirement has too much finality to me." Moore always has been first in. If he gets his way he may be last out as well.

Tom Moore, 75, living the good life.