First Lieutenant Clay Schwabe's plans for August became much simpler last month. Instead of running in the 1,500-meter race at the 2004 Olympic Games, the Army officer and one-time world-class runner will watch from his home in Boulder, Colo.

Two years ago Mr. Schwabe, 25, was one of America's top middle-distance runners-a solid bet to represent the United States in the 1,500-meter run and a dark horse for a medal. But a few faulty stitches scuttled Mr. Schwabe's Olympic dreams. An operation in 2003 to remove a cyst in Mr. Schwabe's left knee led to complications that ruined his chances for the 2004 Olympics and almost kept him from ever walking again.

Clay Schwabe grew up not walking but running alongside his father, an Army officer who jogged to keep in shape. Clay would run everywhere: "If I had to go to the store for my mom, I would just run. If I was with my friends, I would just run." By middle school, he made it to the AAU Junior Olympics. As a junior in 2001 at the U.S. Military Academy at West Point, Mr. Schwabe became the 244th American to run the mile in less than four minutes. He joined the Army's World Class Athletes Program after graduation.

Since then, the Army has allowed him to train full-time-something he says makes him feel "a lot like a professional athlete." Mr. Schwabe figured his times would improve when he was free from West Point rigors and didn't have to make his first run at 5:30 a.m. But last year his career hit a major snag. After running on a sore knee for nearly two months, Mr. Schwabe finally saw a doctor in late February 2003. An MRI revealed a cyst in the outside part of his left knee above the kneecap.

Mr. Schwabe told doctors to cut it out: "If I was an accountant sitting behind a desk, I could have lived with it my entire life. But when you're trying to run fast, it doesn't work that way." Doctors easily sliced out the growth and patched Mr. Schwabe's leg using dissolving stitches. Within two weeks, he started jogging again. By April 2003, Mr. Schwabe traveled with Army runners to the U.S. Olympic training center at Chula Vista, Calif.

"I was just doing some strengthening and a lot of slow buildup," he recalls. "But a week after I got there, all of a sudden my knee started to swell up." A doctor at the training center discovered some of the stitches failed to bind the surgical incision, leaving small gaps at the top and bottom of the wound. The doctor redressed the knee, but Mr. Schwabe already had a brewing staph infection.

After a few more days of swelling and increasing pain, Mr. Schwabe returned to Boulder to his physician. "I flew back in with a 102-degree fever using crutches to walk. There was plenty of pussing and oozing," he said. The next morning he was in surgery and wondering what exactly it would take to make his left knee well: "I thought going in, sure, one more surgery. They've just got to clean it out. It didn't hit me until the third day in the hospital that it was a lot more serious than I thought it was."

Surgeons operated on his knee again to clear out the infection before it could spread to the bone and possibly force an amputation. His fourth and fifth surgeries were to remove scar tissue that had frozen his knee at about a 15-degree angle. But that wasn't the hard part, Mr. Schwabe said: "The physical therapy process that lasted most of the next six months was probably the most painful thing in my life."

By November 2003 when he could jog again, Mr. Schwabe began to train in earnest. With less than nine months before the U.S. Olympic time trials, he scrambled to rebuild his weak leg into Olympic shape. In the process he damaged his right knee, and the subsequent surgery sidelined him for part of February 2004.

Still, with a soldier's determination, the lieutenant reemerged from a half-year layoff and tried to land an Olympic berth. To earn an invitation to the Olympic time trials in Sacramento, Calif., Mr. Schwabe needed to run the 1,500-meter race in 3:41.48. He crossed the country competing in races, desperately trying to make the time. As the July 2 cutoff date approached, he raced in Boston and then in Michigan. On July 2, he made one last try in Bloomington, Ind., at a U.S.A. Track and Field event, but he could not get any closer than four seconds away from qualifying.