Alastair Grant / AP Deena Kastor, an Agoura High graduate, gestures after she crossed the finish line to win the London Marathon last April. Kastor will compete in the Boston Marathon for the first time on Monday.

Since she's likely to run just one marathon in 2007, Deena Drossin Kastor thought she'd choose the most historic of all 26.2-mile races.

The Olympic medalist from Agoura Hills makes her Boston Marathon debut on Monday, tackling the storied course in the first race of this year's World Marathon Majors series.

The annual Patriots Day event will be televised live on the Versus cable network, beginning at 6:30 a.m. PDT, with a rebroadcast at 1 p.m.

"Boston has always been in the heart and soul of probably every marathoner out there," Kastor said. "It seems that it's the icon in this sport, the race that everyone strives to get qualifiers for, to be a part of. So it's always been in the back of my mind."

Last year, she chose to run in London because she felt it offered the best chance of breaking the 2-hour, 20-minute barrier, which she did, winning in 2:19:36. With that goal achieved, "it seemed very easy to choose Boston this year, in hopes of trying to win that."

By virtue of last year's win at the Flora London Marathon, Kastor is fourth in the 2006-07 World Marathon Majors standings, trailing Jelena Prokopcuka (second last year in Boston, first in New York), Berthan Adere (fourth in London, first in Chicago) and Rita Jeptoo (first in Boston, fourth in New York). But while there is another round of Majors races in the fall, and a prize of a half-million dollars for the series leader, Kastor does not plan to run this fall in Berlin, Chicago or New York.

Instead, she'll turn her focus toward next year's U.S. Olympic qualifying marathon which will also be run in Boston, although not on the historic course from Hopkinton to downtown. That the trials course will be different is another reason she chose to run in Boston this year.

"I definitely wanted to get in the Boston Marathon as an event, as a whole, before an Olympic year," she said, "because after an Olympic year, it's hard to tell the way your career goes."

Kastor has trained for Boston in a somewhat different fashion than she did for her most recent marathon, in New York. For the fall race, she focused strictly on training. This time, she mixed in some other competitions, winning at the U.S. cross country championships in February and March's Gate River Run 15K in Jacksonville, Fla., as well as running in the Ekiden marathon relay in Japan.

"All of that just makes our job a little bit more enjoyable," she said. "And I think it was definitely evident in practices (with her Running USA teammates), as we joked with each other and traveling together to races, that we're in this to have a good time, first off, and second to produce some good performances."

Kastor sees Prokopcuka and Jeptoo as the top competition in the Boston field, which is not a new experience, since she faced both in New York, as well.

"I know my work is going to be cut out for me," she said. " These are women that know how to fight and know how to struggle."

Because both finished ahead of her in New York, she feels that "in some way" she's running for redemption. "But I probably feel that way any time I get out there and run. Either defend the title and prove that it wasn't a fluke, or get out there and show that you're stronger than you were the last time around."