Tierney Wolfgram had one simple goal Sunday, one she shared with thousands of other runners at the Twin Cities Marathon. “I just wanted to have fun,’’ the 15-year-old Woodbury resident said. “I couldn’t pass up this opportunity.’’

The sophomore at Woodbury’s Math & Science Academy accomplished much more than that in her first try at the 26.2-mile distance. Wolfgram finished sixth in the elite women’s field, running a time of 2 hours, 40 minutes, 3 seconds. The two-time defending state Class 1A cross-country champion was the youngest woman in the top 25 by eight years, and one of two Minnesota teens to finish in the top 50.

Shoreview’s Sarah Schmidt-Dannert, 19, placed 45th in 3:11:37.

Wolfgram’s time fell short of the U.S. junior record of 2:34:24, set by 16-year-old Cathy Schiro in 1984. According to the Association of Road Racing Statisticians, an independent organization that tracks elite distance-running statistics, the world record for 15-year-old girls is 2:29:41, set in 2002 by China’s Mei-yu Shen.

“It was great,’’ Wolfgram said of her marathon debut. “My half-marathon time qualified me for this, so I had to do it.

“My aunt and uncle have been doing this marathon for the last couple of years, and they always talk about the people that come out. It’s amazing to hear how many people there are, and it’s hard not to smile when you pass them. It made it a lot easier to stay positive.’’

Wolfgram led the women’s field at the first two markers, completing the opening 5 kilometers in 17:32 and the 10K in 35:42. By the halfway point, she had dropped back to sixth.

She laughed about that strategy, saying she didn’t have a time target but probably should not have gone out that fast. Still, she said the excitement of leading the pack was “a fun thing.’’

As an eighth-grader in 2016-17, Wolfgram followed her first state cross-country title with victories in the 1,600 meters and 3,200 meters at the state track and field championships. She earned a second state championship in cross-country last fall, then won the prestigious Nike Heartland Regional and placed seventh at the Foot Locker National Cross Country Championships.

After making such a big impression in her first marathon, she was noncommittal about her next.

“I don’t know,’’ she said. “I’ve got a cross-country season to finish up.’’