Rory McIlroy has first down with a 65 at Augusta

Forgive the Masters today for making sure that Amen Corner hasn’t turned into a mosh pit and its green jackets haven’t become hoodies.

Forgive the Masters today for presenting its first-round coleader with a comb and a word of caution.

“Street football? At night? Really?”

Just as America’s most starched sports event is surely wary of Rory McIIroy, the rest of us should love him. All freckles and biceps and laughs, the 21-year-old Northern Irish mop top was a jolt of youth flowing across the Augusta National course Thursday to the stares of the green-hairs and the howls of the cigar set.

On a billowy blue afternoon, he shot an equally gorgeous 65 in front of kids, pals and many empty seats of those who had walked away to find Tiger or Phil. He had seven birdies and no bogeys during a midday stroll that included almost constant conversations with his two young playing partners about all sorts of important things.

“Cars, boats, anything but golf, really,” McIlroy said.

Masters leaderboard

And, believe it or not, dude, he prepared for this Wednesday night by doing something that is not allowed on this course, or, it turns out, even on his own block.

McIlroy and some buddies drove to a mall. They bought this strange thing known as a football. They went home and began throwing it in the cul-de-sac in front of their rental home.

“Sort of got into American football from being over here, and just wanted to learn how to throw it a little bit better,” McIlroy said.

So, were you running some pass patterns, I asked.

“I don’t even know what that means,” he said.

Alvaro Quiros saves the best for last at the Masters

Ah, but soon he learned about breaking off a route early. With darkness arriving and their voices rising, a neighbor walked out of her house and ordered the kids to knock it off.

“I was actually told off by the lady living across the street; we were making a bit too much noise,” he said. “Had to cut it short.”

The woman spoke not only for herself, but for 75 years of Masters lore. McIlroy, who shares the top spot with Spain’s Alvaro Quiros, is the youngest first-round coleader in tournament history, but at some point, chances are, somebody around here is going to shoo him home.

If McIlroy can hang on for three days, he would become the second-youngest Masters winner. Since Tiger Woods set the record in 1997, only three of 13 championships have been won by someone under 30 -- Woods twice and Trevor Immelman. In 74 previous tournaments, only 17 champions have been under 30.

“But at least for today, Rory couldn’t do anything wrong out there, and it was really nice to see,” said Rickie Fowler, his 22-year-old playing partner, who, with 23-year-old Jason Day, helped turned their threesome into a bit of a walking frat party.

Fowler, a former dirt bike champion from Murrieta, showed up dressed entirely in green, even the oversized cap that smothered his unruly hair. It looked hideous, which, of course, meant Fowler thought it looked cool.

When asked if that color was Masters green, Fowler chirped, “That was the only reason we made it ... how is that?”

When asked how he would wear that awful cap if he won the tournament, he said, “Well, around here, it’s forward. Once I get off -- if I had a chance, I might throw it on backward.”

It was that sort of hip day at the old course, twentysomethings such as coleader Quiros (28) and Charl Schwartzel (26) also among the day’s best dozen golfers. But that group also included former PGA champion Y.E. Yang sitting just two strokes behind, and defending champ Phil Mickelson is lurking five strokes back.

A majors leaderboard is generally no place for children, as McIlroy discovered last summer after he posted a record 63 to begin the British Open, only to be blown away the next day by shooting a windy 80.

“I know better than anybody what can happen to the first-round leader of a major,” he said, shaking his head while walking off the course.

He wound up tied for third in the British Open and the PGA Championship, and starred for Europe in the Ryder Cup, so his emergence here should be a surprise to few, especially him.

After all, he is the first young player so openly unafraid of the once almighty Tiger Woods.

Before last year’s Ryder Cup, McIlroy said of Woods, “I would love to face him.”

In a recent essay for Sports Illustrated, he wrote of Woods, “I’m not sure we are going to see him dominate again the way he did. ? He’s playing like an ordinary golfer.”

I can now second that opinion.

As I walked the course in search of McIlroy early Thursday afternoon, I was stopped by a threesome playing several hundred yards down the fairway. The crowds were small and solemn, and it wasn’t until one person shouted, “Go Tiger” that I realized Woods was one of the golfers.

Woods, who hasn’t won in 17 months, finished the first round tied for 23rd with perhaps his quietest 71 ever. It’s truly as if he’s become just another Nike shirt.

I watched Woods pass and continued on my way, following the trademark Augusta roars, which are surely blushing today at being described as Rorys.

bill.plaschke@latimes.com

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