There was no doubt when he hit it.

As the ball rocketed off Mark McGwire’s bat in St. Louis on Monday, fans across the world joined the Busch Stadium chorus of 50,000:

“Get over the fence,” they pleaded. They were not disappointed.

McGwire’s 62nd home run, lined to left field, ended his chase of Roger Maris’ record of 61 home runs in a season, set in 1961.

While players from both teams erupted out of their dugouts, the burly Cardinal raised his fist, trotted around the bases and bashed forearms with his third-base coach — not too unusual.

But in this desert-like era of spoiled, $120-million athletes, McGwire was a refreshing oasis as he crossed home plate.

A smile washed across his face, showing pure joy and, undoubtedly, a season’s worth of relief.

Yes, Mark McGwire was having fun — what a novel concept.

Then, his 10-year-old son flew into his arms. Matt McGwire was serving as the Cardinals’ bat boy Monday and had a front-row seat for his father’s day in history.

A kid? On the field? Sharing baseball with his dad? Inept commissioner-for-life Bud Selig surely didn’t orchestrate this one.

Another absolutely touching moment followed. McGwire pointed to Maris’ sons, seated in the box seats along the first-base line.

Sunday, he had raised his hand to the sky, recalling the spirit of the Yankees’ right fielder, and then placed his hand over his heart and patted his chest.

But on Monday, he simply ran over and hugged each member of the family.

The macho image of a home-run hitter disappeared in the reverence of an unrehearsed gesture to a baseball ancestor.

Sammy Sosa, the man chasing McGwire in the home run race, is equally selfless.

At a pre-game press conference Sunday, he ducked the spotlight, saying of McGwire, “He’s the man in the United States. I’m only the man in the Dominican Republic.”

After a strike four years ago nearly strangled the life out of America’s pastime, the drama of power versus power has almost resuscitated it.

Can McGwire and Sosa reverse the calamity inflicted by Selig and his partner-in-crime Donald Fehr?

It’s too early to tell.

But in the meantime, don’t miss a minute.

Baseballs are flying out of parks at an astonishing rate, records are falling and a grown man is showing his son the love of the game.