Sasha Cohen's career has been dogged by "ifs." If she had landed one triple toe loop less than 25 seconds from the end of her free skate three years ago at the U.S. Figure Skating Championships, she might have upset Michelle Kwan for her first national title. If she had skated better in Salt Lake City, she might have an Olympic medal instead of a fourth-place finish. If she could skate a clean program, she could become one of figure skating's greats.

At 18, Cohen is one of the more intriguing skaters in recent U.S. history. She possesses incredible flexibility, maneuvering her 5-foot-1 frame into yoga-like positions. And she has proven that she has the athletic ability to compete with some of the best, too. In practices, she even has landed quads -- four-revolution jumps that one woman has landed in competition -- although she has not attempted one in competition this season.

What Cohen has not done is put all of her strengths together at one time, and that is what she hopes to do at the world championships.

"Hopefully," said Cohen, who was fourth at worlds last year, "it's an opportunity not to regret."

Cohen is not sure whether she is a favorite or an underdog going into worlds. She has been one of the strongest competitors in the world this season, claiming two victories on the Grand Prix circuit before defeating 2002 world champion Irina Slutskaya in the Grand Prix Final in St. Petersburg.

On the other hand, she finished a disappointing third at the U.S. Figure Skating Championships in January in Dallas behind Kwan and Olympic gold medalist Sarah Hughes. Cohen, who skated a flawed long program, was so distraught that she had a difficult time composing herself in a post-event news conference.

"Sasha has to show that she can do it when the pressure is on," said 1968 Olympic champion Peggy Fleming. "We'll have to see if she has it mentally. She will be unbeatable if she can transfer that over."

In a sport where perfection is the goal and every aspect of a skater is scrutinized, the mental challenges are as trying as the physical ones. Cohen admitted recently that she has put extra pressure on herself because her family made a cross-country trek from Southern California to snowy Connecticut so she could train with Tatiana Tarasova. Cohen previously had worked with John Nicks. Last summer, Cohen and her family moved.

However, Cohen said the lessons she learned from Tarasova so far have been invaluable, remarking that Tarasova helped her with everything from refining her technique to improving her mental approach. Tarasova has coached several champions, including 2002 Olympic gold medalist Alexei Yagudin.

"I'm happy with the direction my skating career has gone this season," Cohen said.

The true test will come, however, next week. The main battle likely will come down to three Americans -- Kwan, Hughes and Cohen -- especially now that Slutskaya has withdrawn. That is not to say that it will be easy for the Americans to sweep. Don't count out Japan's Yoshie Onda and Fumie Suguri and Russia's Elena Sokolova.

To win, Cohen will have to skate well in three programs -- as opposed to nationals in which skaters perform two routines -- because there is a qualifying round. The qualifying skate counts for 20 percent of the final score. (The short program is worth 30 percent; the free skate is 50 percent.)

"When I go to Washington," she said, "I'll be looking at putting out my personal best, because that's something I feel I haven't really done this season."

Sasha Cohen's flexibility has helped her ascend to top tier of skaters. She was fourth at Salt Lake City Olympics and 2002 worlds. Spin control: U.S.'s Sasha Cohen "has to show that she can do it when the pressure is on," Peggy Fleming said.