Julie Zetlin performs with the ribbon during the 2007 Pan American Games. The Bethesda native is the U.S.’s best chance of avoiding being shut out of the rhythmic gymnastics competition at the 2012 London Olympics. (EVARISTO SA/Agence France Presse/GETTY IMAGES)

The last thing Bethesda’s Julie Zetlin wanted to hear on the eve of the biggest summer of her rhythmic gymnastics career was these three words: You need surgery.

Zetlin, a U.S. national champion in a sport in which the United States has struggled internationally, reluctantly followed her doctor’s recommendation in early May.

Rehabilitation from the operation to repair a torn meniscus in her right knee took longer than expected. She was forced to withdraw from the U.S. championships in August. She couldn’t jump until about a month ago.

Yet, beginning at this week’s world championships in Montpellier, France, she is tasked with nothing less than saving the U.S. rhythmic gymnastics program from a second straight global slip-up.

Four years ago, the U.S. rhythmic program failed — for only the second time since 1984 — to qualify for the Summer Olympics. Bum knee or not, Zetlin’s primary goal between now and January, when the final qualifying spots will be doled out in London, is to make sure that doesn’t happen again.

Despite losing weeks of training this summer, she said she is physically ready for the start Monday of the world championships, where 15 Olympic qualifying slots will be on offer. On paper, she provides the United States with huge hopes; last year in Moscow, Zetlin became the first U.S.-born rhythmic competitor to qualify for a world all-around final.

“Now, I feel really great,” Zetlin, 21, said from Paris during a conference call Monday. “I feel pretty prepared. I feel strong mentally, physically. . . . I think the biggest thing for me to show is . . . my ability to be consistent. If I show my strength in that, I think I have a pretty good chance of advancing to the Olympics.”

Yet Zetlin wants to block out the stakes, focusing on clean routines rather than counting placements.

The numbers could get harrowing. Despite making the final in Moscow, Zetlin finished 23rd overall. If she falls short at the championships that conclude Sept. 25, she will have another chance during a January pre-Olympic event in London. And with a strong performance at next month’s Pan American Games in Guadalajara, Mexico, she could position the United States to receive a wild-card entry.

“We have two sets of qualifiers and chances to get me over to London,” she said.

And at least the summer is nearly over. Because she underwent a similar knee surgery when she was 15, Zetlin figured she would be back at full speed by early June. Yet she didn’t feel healthy enough even to tackle the Aug. 17-20 Visa Championships in St. Paul, Minn. Her last-minute withdrawal forced her to petition for a slot on the world championship team.

Zetlin, who trains under Olga Kutuzova at Rhythmflex in Gaithersburg, said she spent weeks at the U.S. Olympic Training Center in Lake Placid, N.Y., taking advantage of the the center’s equipment and on-site physical therapist.

“It was kind of an uphill-and-downhill-type battle,” she said. “When [my knee] wasn’t recovering as fast as I thought it would have, it was a little bit frustrating and getting me down. I just had to remind myself . . . ‘Don’t rush the recovery process; then you’ll be okay.’ ”

Though Zetlin did not start attempting her trademark powerful jumps until August, her spirits soared when Kutuzova told her she was getting more amplitude pushing off of her reconstructed knee than before the surgery.

“In some ways, I got even stronger,” she said. “With every negative I think you can turn it around into a positive.”