Lindsey Vonn: What her exit means for the Olympics

Lindsey Vonn arrives for training for the Women World Cup Downhill on Dec. 18, 2013, in Val d'Isère, France.
Franck Fife | AFP | Getty Images

Unable to overcome the severe damage suffered to her right knee in a ski crash last year, gold medalist and media star Lindsey Vonn said Tuesday she's out of next month's Sochi Olympics.

Vonn's withdrawal from the Winter Games is not only a blow to U.S. efforts in the medal race, but it could also mean lower TV and online ratings, especially from American audiences.

"She's highly marketable, and without her I would expect interest in the games from U.S. viewers to drop," said Mark Conrad, professor of sports law at Fordham University.

"Given the time difference on when the games are aired even live in the U.S., there's enough difficulty in getting viewers, but her not participating makes it worse," Conrad said.

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The 29-year-old Vonn had been the face of NBC's marketing efforts in promoting its broadcasts of the games, and her return from the knee injury was a big story in the sports world (NBC Universal is the parent company of CNBC.)

But that's pretty much over now.

"There aren't that many well-known American athletes in the games, and she was probably the major draw," Conrad said.

Vonn matched a pretty face with a winning attitude, said Brad Adgate, senior research analyst at public relations and marketing firm Horizon Media.

"She's every photogenic and had a high profile," Adgate said.

"Americans love a winner and she won," he added. "I think they'll still watch the games but her loss will be felt."

Political drama at Sochi Olympics

Vonn is considered the most accomplished female skier in American history. She's won 17 World Cup titles, including a record six consecutive downhill titles and four overall crowns.

She holds 59 World Cup victories and was set to defend her gold medal in the downhill from the 2010 Olympics.

From all those wins, Vonn has signed to numerous endorsement contracts, including with sponsors Under Armour, Alka-Seltzer, Procter & Gamble, Red Bull and Rolex.

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She was listed as the 42nd-most marketable athlete in the world after 2010 and is said to have a net worth of $3 million, mostly from her endorsements.

Vonn also had to pay some $1.7 million in back taxes to the federal government in 2012. The divorced Vonn currently has a high-profile personal relationship with golfer Tiger Woods.

Conrad said it's unlikely that Vonn's exit from Sochi will hurt her marketability in the future.

"She does plan to continue competing after the games are over and she's recovered. So while she's missing some opportunities by not being at Sochi, it won't hurt her all that much," he said.

Securing Sochi: Protecting the Olympics

In a statement Tuesday, Vonn said:

"I am devastated to announce that I will not be able to compete in Sochi. I did everything I possibly could to somehow get strong enough to overcome having no ACL but the reality has sunk in that my knee is just too unstable to compete at this level.

"I'm having surgery soon so that I can be ready for the World Championships at home in Vail next February. On a positive note, this means there will be an additional spot so that one of my teammates can go for gold. Thank you all so much for all of the love and support. I will be cheering for all of the Olympians and especially team USA!"

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Conrad said Vonn's sentiments could be a forecast for an Olympics without her.

"It does create an opening for someone else to step up and be a new Lindsey Vonn," he said. "There's always a need for a new star."

—By CNBC's Mark Koba. Follow him on Twitter @MarkKobaCNBC.