Carl Rundell thought he knew about all of the runners capable of winning yesterday's Marine Corps Marathon. He researched their times and knew that, after finishing fifth last year, he had a good chance of winning.

But as Rundell led the group of almost 30,000 runners, there was one man alongside him he didn't know. The man in the navy blue tank top and shorts was matching his pace, and he wasn't going away.

Ruben Garcia stayed with Rundell for about 20 miles before leaving him behind. Garcia then spent the last several miles of the 26.2-mile race simultaneously battling his cramped left hamstring and holding off Rundell. He did both successfully and finished in 2 hours 22 minutes 14 seconds -- nine seconds ahead of Rundell -- and won the 30th Marine Corps Marathon with the fastest time since 1997.

Garcia told reporters through an interpreter that his "objective was to win" and added that he was satisfied after holding off a determined Rundell.

Susannah Kvasnicka, 33, from Great Falls, was the first woman to cross the finish line. She ran the Twin Cities Marathon four weeks ago and began yesterday's marathon ready to drop out if she didn't feel physically capable of running a strong race. Instead, she earned her first career marathon victory by finishing in 2:47:07, almost three minutes ahead of Eugene, Ore., resident Liz Wilson.

"I just thought I'd come out and see what happens," Kvasnicka said. "But I felt pretty good at 10 [miles] and just decided to keep going."

Garcia, 34, said the only two marathons in which he competed this year before yesterday were in Mexico -- likely the reason he evaded Rundell's scouting report. But Garcia's experience in Mexico didn't work entirely to his advantage. The corporal in the Mexican navy found running yesterday's course, which began near the Arlington Memorial Bridge and wound through the District, slightly more difficult than ones to which he is accustomed.

He said his "legs felt like they were giving out because of the hills."

Garcia, who lives in Mexico City and trains at relatively high altitudes, was also adversely affected by yesterday morning's chilly air. The temperature hovered around 40 degrees at the start of the marathon's first wave of runners, a level much cooler than the 60-degree weather Garcia prefers.

"It was harder to breathe," he said.

Whatever discomforts affected Garcia, they hardly showed. He and Rundell assumed the lead during the first quarter of the race, and both reached the 10-kilometer (6.2-mile) mark in 34:34.

It was approximately at this point that third-place finisher Eric Post, 26, of Centreville, fell back for good.

"They started hammering, and I've got to be honest with you, I thought they were going to come back," Post said. "Looking back I would have covered that move because they opened that gap on me and that was it. I couldn't close the gap."

Rundell, an independent management consultant from Birmingham, Mich., was surprised and impressed by Garcia's ability.

"I did my homework and knew sort of where [the top runners] were going to fall in," Rundell said. "He stuck with me the whole way. . . . I had no clue who he was."

Rundell's unfamiliarity with his opponent's running style prompted him to test Garcia. They traded the lead several times before Rundell, with the Lincoln Memorial in sight, tried to press Garcia with a 5:10 mile at the halfway point.

Garcia was up to the challenge.

"I was trying to figure out what his strengths and weaknesses were going to be at the end of the race," Rundell said. "I threw in a 5:10, a 5:13, and that was into the wind, to try and drop him, and he just stood right there.

"I thought if I get a big enough gap, he's going to have to work to keep up. And I thought, okay, I'll see if he stays with me. He dropped a little bit but then he was right back up.

Garcia and Rundell stayed close to each other for approximately seven more miles before Garcia made his move. He stretched his lead to about 15 meters during the 20th mile, just before the 14th Street Bridge.

Rundell, though, didn't let Garcia pull away. He tried to erase the distance between them like Garcia had done before, but he simply couldn't.

"Unfortunately, he had a little bit more of a kick toward the end," Rundell said. "Every time I would catch up and close the gap, he would just pick it right back up again."

Maintaining the lead wasn't easy for Garcia. At Mile 23, his legs began to cramp, particularly his left hamstring. He said afterward that he would have dropped out of the race if his hamstring had tightened up much more.

But with Rundell close behind, Garcia refused to give in to the pain. He kept Rundell at bay, knowing that any lag in his pace would cost him the lead.

"When you run a marathon, anything can happen at any point," Garcia said. "You don't win until you cross."

Garcia was low-key when he crossed the finish line, becoming the first Mexican to win the Marine Corps Marathon since 1996.

Rundell, who led last year's Marine Corps Marathon for 24 miles before falling back, lamented his inability to finish as strongly as Garcia.

"I was running at my max," Rundell said. "I was not out of my range. At the end, I definitely threw everything I had. But everything I had was not much."

Ruben Garcia of Mexico wins in 2 hours 22 minutes 14 seconds, the race's fastest time since 1997. "I had no clue who he was," runner-up Carl Rundell said.Marine Capt. Paul Duncan takes pictures of the scene at the starting line of the 30th Marine Corps Marathon. Christine Stier of Bedminster, N.J., gets some help just before the finish line.