"I'd been wanting to run a longer race for quite some time," Flanagan said. "I was really excited, but I kept the nerves in check."
Teshome Gelana, of Ethiopia, won the Chevron Houston Marathon in a course record 2:07.37. Brett Gotcher was the top American, finishing in 2:10.35 in his first marathon.
Defending champion Teyba Erkesso, also from Ethiopia, won the women's marathon in 2:23.52. She beat her own course record by almost 30 seconds. Paige Higgins was the top American, finishing fourth in 2:33.22.
Flanagan won bronze in the 10,000 meters at the Beijing Games and was entered in a race longer than 10,000 meters for the first time. The 28-year-old was using the event Sunday as a springboard toward preparing for the 2012 Olympics in London.
"It was a lot of fun, but a little nerve-racking in the middle of the race," she said. "I might have had a patch where I was like, 'Oooh, can I really sustain this?' But then I got into a groove and clicked the miles away. I just settled in and got comfortable."
Antonio Vega of St. Paul, Minn., won the men's half-marathon in 1:01.54.
The races began under clear skies and a temperature of 42 degrees.
