For more than 80 miles, dozens of world-class women riders tested there resolve in the wind and heat surrounding Mankato, Minn., in the fourth stage of Great River Energy’s Nature Valley Grand Prix on Saturday.

But the most exciting action of the day came with the final few laps in the city. With Olympic champion Sarah Ulmer of Jazz Apple opening a 20-second gap more than a lap into the finishing circuit, a win seemed assured.

That was until the overall leader, TEAm Lipton’s Kristin Armstrong, decided to put her stamp of authority on a victory. Attacking on the third time up the Main Street hill that pitched at 14 percent, she pulled away from the competition to take the stage and increase her lead over Webcor/Platinum Builder’s Christine Thorburn.

Armstrong, one of the strongest riders in the women’s peloton, said it was both sensing the time and a bit of luck that gave her the win.

Ulmer takes a dig

Photo: Casey B. Gibson

“As we started up that hill a third time, I could sense some of the other girls getting tired,” she said. “I mean, I was tired too, but I find that when the competition is waning, you have to find that something extra and that is what I did today.

“With Sarah going the way she was at the end, I just got lucky to be in the right situation and push out in front.”

And, as usual, she brought the win back to her teammates’ efforts.

“Being here with these eight girls makes all the difference.” Armstrong said of her TEAm Lipton teammates.

The race began extremely close, with no riders seeming to want to break away early. Just after the 37-mile mark, a group of about seven finally pulled away from the main group. Among this group were Colavita/ Cooking Light’s Gina Grain and the powerful TEAm Lipton’s Katherine Lambden. The break was short-lived, with the field catching them at the 42-mile mark.

A final group of about 64 riders remained until the 77-mile mark and the start of the circuit race through Mankato, which included the treacherous Main Street Hill. Ulmer broke out ahead and built a 20-second lead over the field. It was during the third lap that TEAm Lipton once again flexed its muscle and catapulted Armstong to the front.

Get this woman an iced tea!

Photo: Casey B. Gibson

Armstrong then put on a clinic as she upped her lead and cruised to a comfortable victory over second place finisher and TEAm Lipton teammate Kori Seehofer. Alex Wrubleski of Team Biovail took third.

Webcor-Platinum Women's Cycling’s Erinne Willock had another strong showing, maintaining her BMC Best Young Rider Jersey. Ulmer was awarded the SportsPro Most Aggressive Rider Jersey for her work in the final laps around Mankato. That climb also earned her the Jelly Belly Sports Beans Queen of the Hill Jersey.

With Saturday’s stage win Armstrong adds to her lead going into Sunday’s Stillwater Criterium. Armstrong knows that the Nature Valley Grand Prix is far from over.

“Tomorrow is going to be tough,” she said of Sunday’s crit, which includes the infamous Chilkoot Hill that pitches at 24 percent and is the finish for the circuit.