For 15 years, Jared Fogle was Subway’s greatest success story.

Now, Subway would rather customers forget it ever had anything to do with him.

On Wednesday morning, federal documents said the now-former company spokesman planned to plead guilty to charges of distributing and receiving child pornography and engaging in sex acts with minors.

It’s a nightmare situation for any company, and Subway’s link to Fogle was tighter than many business-pitchman relationships. The company heavily relied on Fogle – who is married with children – for years, correctly guessing that his regular-guy demeanor and do-it-yourself diet plan of cheap fast-food sandwiches would resonate with its customers.

According to AdAge, same-store sales dropped 10 percent in 2005 after Fogle’s advertising contract expired and his ads stopped airing.

The charges against the one-time face of the sandwich chain will have an effect on the brand, but not long-term, said Ira Kalb, assistant professor of clinical marketing at the USC Marshall School of Business.

“Subway didn’t do anything wrong,” he said. “It’s somebody associated with Subway that did something wrong.”

He added: “I think people have short memories, and they’re probably going to forget this pretty quickly.”

The Milford, Connecticut, company has distanced itself from Fogle over recent months.

In July, Subway said it and Fogle had “mutually agreed to suspend their relationship” after federal agents seized documents and electronics from his Indiana home.

On Tuesday, Subway tweeted that the company no longer had a relationship with Jared and that it had no further comment.

Kalb said the situation with Fogle highlights the dangers of relying on company spokespeople to represent a brand. A mascot, like the Charmin bear, is a safer choice.

“When spokespeople get into trouble, or things come out about them, it’s definitely going to have some spill over to your brand,” he said. Mascots “don’t get into trouble.”

According to the official story, Fogle once weighed 425 pounds and was unable to walk across the campus of Indiana University.

After switching to a diet that included two Subway sandwiches a day, as well as increasing his exercise, Fogle lost more than half his body weight in less than a year.