While keeping up with the Kardashians is hard enough, Bruce Jenner thinks keeping up with U.S. gold medal hopeful Ashton Eaton in the decathlon might be even harder.

Before he gained reality television fame as the stepdad of Kim, Khloe and Kourtney Kardashian, Jenner was a 1970s icon when he won the gold medal and set a world record in the decathlon at the 1976 Olympics in Montreal. Even in his prime as an athlete, however, Jenner believes he wasn’t on the level of Eaton, who will compete for decathlon gold in London on Wednesday. Making his first trip to the Olympics since the 1996 Games in Atlanta, Jenner is serving as a special E! News correspondent in London and raved about Eaton on TODAY Tuesday.

“(Eaton is) the greatest decathlete we have ever produced,’’ Jenner said.

Eaton set the decathlon world record with 9,039 points during the U.S. trials last month. American Bryan Clay won the decathlon gold in the 2008 Olympics with a score of 8,791 points, and Jenner’s career best was 8,634 points. Eaton’s performance last month makes the 24-year-old Oregon native the heavy favorite in a sport that encompasses 10 track and field events, from long jump to the 110-meter hurdles. He hasn't even matched Jenner's feat of winning the gold medal yet, but Jenner already believes he is better than any who have come before him.

“I’ll take any athlete you know, any sport, training for 10 years – he cannot do what Ashton Eaton will do in the next couple of days,’’ Jenner said. “The most phenomenal athlete I have ever seen.’’

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Jenner was considered a phenomenal athlete himself during his heyday. He also is one of the first Olympians to enjoy the marketing bonanza that comes with winning gold, as he famously graced the front of Wheaties boxes. Now he is more well-known as the stepfather of the Kardashian clan, but has no problem with the younger generation recognizing him as an exasperated TV dad instead of a decorated athlete.  

“My generation, our group, they kind of know you from the old days, for all the Wheaties commercials and the games and all those things I did, but certainly the younger group, primarily female, it’s all about being Kim, Kourtney and Khloe’s dad, which is fine with me,’’ Jenner said. “Being a parent is more important than winning gold medals.’’

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Unlike the thousands of Olympic athletes hoping to publicly smash records this week, Harry Nelson has quietly spent his life setting his own.

For this 90-year-old, his reward won’t be a gold medal, but a spot in the Guinness World Records for attending the most summer Olympic games. London marks his 18^th time as an Olympic spectator.

Nelson attended his first event as a child when the Summer Games came to his neighborhood.

“At age 10, something called the Olympics had come to Los Angeles where we lived. I didn’t know what that was but, of course, as time went by, we understood,” he told TODAY’s Al Roker and Natalie Morales.

Following those games, Nelson said he, his brother and cousins built their own “Olympic field” in a vacant lot next door to their home.

“We had a track, we had our pole vault with a little bamboo pole and a high jump,” he said. “We had a discus — we used a wagon wheel for our discus.”

In the decades since, Nelson has saved money in various ways for his trips — including collecting change in a mason jar and selling his car to his uncle when he was in college.

Nelson's company during most of the Olympic trips has included his wife, Delores “Dee” Nelson. The London trip is her 12^th Summer Game. She made her first Olympic trip in 1956 to Melbourne in what ended up being a delayed honeymoon for the couple.

She told TODAY she doesn’t have a favorite sport although she and her husband favor the track and field events.

“That’s what attracted us together, because we started going to the Coliseum relays in L.A., and that led to the Olympics,” she said.

The Torrance, Calif., couple were among the few Americans who attended the 1980 Moscow Games, despite the U.S. boycott and a letter from then-President Carter discouraging them from going.

In 2008, Nelson self-published a book about his Olympic experiences, "Following the Flame: A 76-Year Olympic Journey."

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