EUGENE — The Oregon Duck — the Duck — was onstage, sitting between four men in suits while wearing a jaunty hat, a neckerchief and no pants. The Duck poured Froot Loops and milk and a pound of sugar into a bowl, then pretended to eat it. Crystals of sugar cascaded because, of course, the Duck has no lips.

“College GameDay,” ESPN’s traveling pregame show, was on campus Sept. 6 for No. 3 Oregon’s game with No. 7 Michigan State. At the end of every show, the hosts predict the winner of the day’s top games. The Duck pantomimed his picks — holding an elephant for Alabama, donning a leprechaun’s hat for Notre Dame, shooting a foam rocket for Toledo. The hosts giggled their way through their analysis and prognostications.

“Sometimes you pick like Daffy Duck,” Lee Corso said to the Duck.

That insult might have struck viewers at home. They might have wondered, but probably did not, just why the Oregon Duck looks like Donald Duck, but in a different-colored sailor’s ensemble.

The short answer: because he is Donald Duck.

It has been this way since 1947. By then, the university’s original nickname for its sports teams, the Webfoots, had morphed into Ducks. Live ducks, usually named Puddles, took turns patrolling the sideline during games. But in the 1940s, Oregon wanted a consistent Duck image.

The university was in luck because Oregon’s athletic director at the time, Leo Harris, was a friend of Walt Disney’s. Disney told Harris that the university was welcome to use Donald Duck, who debuted in 1934, as the mascot, provided it was in good taste.

And so Oregon did — first in renderings and logos, including a Donald poking out of an Oregon “O.” Eventually, the costumed mascot came to look quite a bit like Donald, too.

After Disney died in 1966, officials realized that there was no formal agreement between the parties to share the image of Donald Duck. But Oregon produced a photograph of Disney wearing an Oregon letterman’s jacket, with the Donald Duck logo on the chest, and a written contract was signed in 1973.

On merchandise, the Donald Duck logo can be hard to find these days. Part of the agreement with Disney was to restrict the sale of the Donald logo to mostly around Eugene and Portland, said Craig Pintens, the university’s senior associate athletic director. Oregon’s primary logo is a stark yellow, duckless “O.”

But the live costumed character, wildly popular at events like Saturday’s football game against Wyoming (and available for appearances at $300 per hour), came to look more and more like Donald.

For a university that sells its sartorial soul to the whims of Nike, assembling a new combination of psychedelic colors on the uniforms nearly every game, the Duck stands out for his indifference to style.

There have been pushes now and again to toughen his look, to make him a snarling duck or a fighting duck, maybe even put pants on him, but tradition has held.

Although the mascot’s biography calls him Donald, Oregon officials call him the Duck, as if to distinguish the characters. And they might point out that the two are not identical.

Besides the color schemes of their minimalist naval attire, their clothing has slight variations, from the style of headwear (the Duck wears a sailor hat, while Donald Duck has a fluffy beret with a ribbon) to the stripes on their cuffs (two for the Duck, one for Donald). And the Duck is in better shape — leaner through the hips.

But the biggest difference is in the eyes. Donald Duck has small oval pupils resting at the bottom of his giant eyes. The Duck’s pupils these days are round and big, as if he were stuck in a dark closet. And Donald Duck speaks in a spittle-spraying lisp; the Duck is mute.

On Saturdays, “College GameDay” reaches its climax when Corso unveils his choice in the day’s big game. Typically, he reaches under the table, grabs the costume head of the mascot of the team he thinks will win and puts it on his head.

This time, the Duck reached under the table and handed Corso a wrapped package. Corso tore into it, revealing a Duck head. Hundreds of fans surrounding the set cheered as Corso put the Duck head on his own.

Now there were two identical Ducks, wide-eyed and familiar, and they hugged.