The true American sports explosion took place in the 1970s. The examples of this are plentiful.

The NFL-AFL merger became complete in 1970 with 24 teams, and there were 28 at the end of the decade. The NHL went from 14 teams to 21. The NBA went from 14 teams to 22. The NCAA men's basketball tournament went from conference champions and invited independents (22 to 25 teams) to 48 at the start of the '80s.

Title IX came into effect and put women into the sports arena. The North American Soccer League boomed, then busted, but it made many more Americans familiar with this odd, hands-free activity.

The first World Series night game was played in 1971. The NCAA basketball title game was moved from Saturday afternoon to Monday night in 1973.

There are two happenings that had as much to do with these large changes in our SportsWorld as any other:

The launch of "Monday Night Football" at the start of the decade, Sept. 21, 1970, and the launch of ESPN at the end of the decade, Sept. 7, 1979.

"That wasn't the connection we made when we put this together, but that's a good thought," Chris Berman said. " 'Monday Night Football' turned sports into a prime-time attraction, and ESPN turned sports into a daylong attraction."

"Monday Night Football" moved from ABC to its cable partner, ESPN, in 2006. The series kicks off its 48th season Monday night in Minneapolis, with the Saints and the Vikings in the first game of a doubleheader.

Additionally, it will be the kickoff of "Boomer's Vault," a three-minute piece on the pregame "Countdown" show and the first installment in Berman's season-long ode to "Monday Night Football."

"I'm not going to have a physical presence on 'Countdown' now, and this was an idea we all came up with at ESPN," Berman said. " 'Why don't we do something to remind us of amazing events that have taken place surrounding "Monday Night Football"?'

"They opened up the vault, close to a half-century of games, and told me to pick the story."

Often, Berman's feature will involve one of the teams in the game, but not always.

"There are no rules; what we're going to do is evoke memories," he said.

One of Berman's more poignant memories came on Sept. 25, 2006, the third Monday since those prime-time games moved to ESPN.

"That was the night that the Saints returned to the Superdome after Katrina," Berman said. "I'll go to my grave remembering the emotion in the city and the stadium for that game.

"I picked this for the first 'Boomer's Vault' a few weeks ago. And now with what Harvey has done to Houston … it's amazing that will be the first one."

And with what Irma might have done to Florida and elsewhere by Monday night, the lesson of a football team coming back home to help revive the spirit in a city could be even more poignant.

"The Saints beat the Falcons 23-3 that night," Berman said. "You remember what happened early in that game? Steve Gleason blocked a punt and the Saints recovered it in the end zone. And today we all know of Steve's tremendous will in dealing with ALS, and now the terrific film 'Gleason.'

"You go back and look at these things, and all the elements that can be there, and it's incredible."

Berman can go back to the incredible start of ESPN. There were no cord cutters to deal with then; one reason being, there weren't many cable cords to cut.

"I ran into Leigh Montville [from the Boston Globe] at a game and he said, 'I see the trucks; they are in the neighborhood; saw one right around the corner yesterday.It's coming, cable is coming.' "

Berman said, "He was right."

He was hired at ESPN two weeks after the launch. A big reason was that he was in the neighborhood, a 25-year-old doing weekend sports at WVIT in Hartford, Conn.

ESPN's new headquarters were 19 miles away in Bristol. With Thursday as ESPN's 38th anniversary, we can recall again what it was like at the start, through Berman:

"There was no plumbing for a week or two. There was no control room. It was raining all the time. We went through ankle-deep mud to get into the building.

"There were seven of us who were on air. I was junior, so I went in at 7 p.m. and worked until 4 a.m. I had a half-hour sportscast at 3 in the morning. I hoped some people on the West Coast were watching it.

"We rode cable's coattails, and it rode ours. The Big Three for cable were us in 1979, CNN in 1980 and MTV in 1981."

As with most national broadcasters, Berman has his share of critics, but there's no mistaking where "Boomer" stands in the history of ESPN's boom. When you hear people using in conversation the nicknames they heard from you, that's quite the impact.

Berman was in Ireland playing golf this week. He'll be on ESPN Radio's No. 2 team for the baseball playoffs with Rick Sutcliffe. And he has more "Vaults" to complete for later in the season.

" 'Monday Night Football' is one of the great TV franchises of all time," he said. "We've unearthed so many things. You'll love Week 2 … same date, Sept. 18, in 1978, Colts-Patriots, and it's 13-7 Patriots going into the fourth quarter.

"Then Joe Washington throws a 54-yard touchdown pass, catches a touchdown pass, and then wins the game with a 90-yard kickoff return. And Howard Cosell says, 'What a football game this turned out to be.' "

As Berman and all "MNF" longtime followers understand, this was Howard simply telling it like it is.

Patrick Reusse can be heard 3-6 p.m. weekdays on AM-1500.