Who was a better performer, Enrico Caruso or Rodney Dangerfield?

Huh?

One was a world-renowned operatic tenor who achieved international fame as one of history's first recording artists, was born in Naples, Italy, and died there a hundred years ago. The other was a stand-up comic who took on the persona of a sad-sack loser who "got no respect" and was born on Long Island, New York, the same year the other guy died. One can assume that Rodney and Rico didn't have a whole lot in common. Oh, sure, they both practiced their professions from stages before large audiences, Caruso in the world's great opera houses, and Dangerfield in some of the country's most infamous gin joints; but beyond that, they weren't very much alike.

Then why compare the two? This, in fact might be the first time ever that their names have appeared in print in the same sentence -- and it might very well be the last time, too.

It's like comparing apples and oranges -- or Tom Brady and Bill Russell.

Fans compare iconic figures from the sports world all the time. The latest rage is measuring Brady against Russell. Which one was the better champion? They competed in vastly different games that require vastly different skills and balls of differing sizes and shapes, to say nothing of different equipment. In one, a well-padded helmet is a must, plus other padding strategically placed on the body for protective reasons. In the other, just pull on some shorts, a tank top, and a pair of sneakers and you're good to go.

Football and basketball are alike in that they both require outstanding athleticism, but the similarity pretty much ends there. Brady is a great athlete, as Russell was in his day. They both won a fistful of championships, and one can easily imagine either succeeding in the other's sport, though not to the extent he excelled in his own.

It's difficult to picture Russell in helmet and pads, but he'd have made a great wide receiver, though his unique talents as a rebounder and shot blocker would never have been discovered.

Brady, on the other hand, is just about the same size that John Havlicek was and with his intelligence and instincts, it's easy to picture Tom in Hondo's old role as a Celtics' swingman. Well, there is one difference: Havlicek's game was running; he never stopped, and he ran every opponent who tried to cover him right into the ground. Running is the one athletic endeavor at which Brady is not very good. He's not only the oldest quarterback in the National Football league, he's also the slowest -- and by a wide margin. It is interesting to note, though, that Havlicek did excel at football, and at Brady's position; in high school, he was an all-state quarterback in his native Ohio. In fact, Ohio State football coach Woody Hayes begged him to play for the Buckeyes but he was committed to the basketball team.

Anyhow, It doesn't make much sense to compare Tom Brady the football player to Bill Russell the basketball player, especially since they played 50 years apart from each other. Russell, who just turned 87, played his last basketball game in 1969 and Brady, in case you haven't heard, is still going strong.

If we're going to compare players from different eras to one another, they should at least be from the same sport -- and, ideally, have played the same position. Even then, the comparisons are difficult. Take, for example, the greatest center fielders in Red Sox history: Tris Speaker, Dom DiMaggio, Fred Lynn, and Jackie Bradley, Jr. They all played in different eras. Speaker played his last game for the Red Sox in 1915, 25 years before DiMaggio broke in in 1940; DiMaggio's last full season was 1952, 23 years before Lynn's rookie year of 1975; and Lynn left the Sox after the 1979 season, 35 years before Bradley's first full year of 2014.

It's safe to say there is no one alive who remembers seeing Speaker playing for the Red Sox, but he was and is regarded as one of the greatest defensive outfielders of all time. However, the legendary Mel Webb, who covered the Red Sox from 1908-1951 for the Boston Globe and saw them both, judged DiMaggio to be the better fielder. DiMaggio is the only outfielder in American league history to have made more than 500 hundred putouts in a season prior to the schedule being expanded to 162 games.

Lynn was known for his spectacular catches, and Bradley is even more so, but Lynn played when outfielders' gloves had been significantly improved and by Bradley's time they had become virtual baskets. This is not meant to demean them or their accomplishments in any way but to point out that times change. And the way that the game is played changes, too. In Speaker's time, a one-handed catch was a rarity, and in Jackie Bradley, Jr.'s time it is using two hands to catch a ball that is seldom seen.

So let's face up to it, there is no way we can accurately compare players of different ages to one another, even when they played the same game and the same position, much less compare players from different sports plus different ages. It should be enough to say that we witnessed the best of their time when they were playing at the top of their game. For those who remember, the pictures in our minds of Bill Russell blocking all those shots and grabbing all those rebounds grow sweeter with each year, as do the newer ones of Tom Brady hefting all those trophies.

But we just can't help ourselves from making comparisons. Is it Tom Brady or Bill Russell? Bobby Orr or Ted Williams? Muhammad Ali or Tiger Woods? Apple juice or orange juice?

As for me, I'm still trying to decide between Enrico Caruso and Rodney Dangerfield.

- Dick Flavin is a New York Times bestselling author; the Boston Red Sox "Poet Laureate" and The Pilot's recently minted Sports' columnist.