Remember when radio broadcasts of the Indianapolis 500 would head to commercial breaks hyping those 800 left turns as the greatest spectacle in sports?

Then it was the greatest spectacle in racing. Who knows. Maybe for the 2007 race we’ll be downgrading to the greatest open-wheel racing spectacle for the fourth Sunday in May.

Looking ahead, will the race’s 100th anniversary in 2016 be promoted as “The Greatest Century-Old Spectacle In Racing?” (Interesting sidenotes: Tom Carnegie will be 97 and Ruth Buzzi once again will be on the list of attending celebrities).

It wasn’t too terribly long ago that the Indianapolis 500 was the most-watched, most-anticipated, most-talked about sporting event in the world, a veritable Daytona 500/World Series/Masters/NCAA Final Four/Super Bowl cocktail capable of entrancing race fans and novices alike.

Americana in its purest form — warm weather, tailgating, fast cars and United States-born drivers behind the wheel of nearly every one of them — Indy stubbornly refused to fall victim to staleness.

Only change could buckle its knees, and change, as it turned out, packs a pretty mean punch.

Indianapolis Motor Speedway President Tony George, polarizing figure that he is due to an alleged sandpaper personality and his creation of the oft-ridiculed Indy Racing League 11 years ago, has spent the past decade ducking verbal arrows fired by traditionalists.

It’s their opinion that George single-handedly took 80 years of wonderfulness and ushered it to a life-support apparatus.

Most of us don’t lay a warm embrace on change. Indiana has proven that time and time again with the four-class system of girls and boys high school basketball, which made its debut in 1997-98 and continues to have the old guard grumbling under its breath.

Race fans no longer circling the date of the Indy 500 on their calendar. Ask yourself what’s given you a case of the grumbles:

Was it the advent of the IRL? Is it escalating ticket prices? Is it NASCAR’s increased popularity? Is it Indy’s increase in foreign drivers?

Maybe it was “E: All of the above.” Nevertheless, never underestimate this country’s patriotism and the fact that, starting in the mid-1980s, a growing number of open-wheel supporters began coming down with an incurable case of the red, white and ... who’s?

The 1970s and early-’80s when A.J. Foyt, the brothers Unser, Johnny Rutherford and Rick Mears dominated is frequently regarded as Indy’s heyday. Charismatic and courageous drivers and, by golly, they were as American as Big Macs and “Brady Bunch” reruns.

In both 1981 and ’82, four foreign drivers started in the field of 33, meaning that, for every Vern Schuppan, there were seven Gordon Johncocks or Sheldon Kinsers.

By 1989, one-third of the starting grid was foreign. In 1996, the number jumped to 16 drivers. In 2003, not a single American placed in the top five, while two years later, over half the grid (18 cars) found itself manned by foreign drivers. By contrast, a total of 20 foreign open-wheelers competed Indianapolis 500s from 1981 to 1984.