The play of Julie Johnston (pictured) has been a bright spot for the USA in the 2015 FIFA Women's World Cup. (Photo: FIFA via Getty Images)

EDMONTON -- When the United States prepared for the FIFA Women's World Cup, the media spotlight was pointed directly at a cadre of proven veterans. 

The impressive list included goalkeeper Hope Solo, midfielders Megan Rapinoe and Carli Lloyd, as well as forwards Abby Wambach and Alex Morgan.

Defense?  That was a supposed American weak spot.

Instead, it has been featured during the CONCACAF champion’s run to the Group D title (2W-1D-0L, 7 points) and defender Julie Johnston has stood out in a lead role.  The 23-year-old’s superb play has kept Christie Rampone, 39, on the bench except for a 10-minute appearance as a substitute in the 1-0 over Nigeria on Tuesday.

“She’s a stud,” said fellow defender Becky Sauerbrunn.  “No one gets by her.”

U.S. head coach Jill Ellis commented that the 15-time capped Johnston "has been a tremendous player in our youth system and has been very, very solid.  An opportunity presented itself with two injuries, so now she’s getting the starting nod in big games, and she’s risen to the level.”

Heading into Monday's round of 16 game against Colombia, the Americans have allowed only one goal -- in the 3-1 opening win over Australia.  Since then they have keep foes out of the net for 241 consecutive minutes.

“As a back line, that’s our ultimate goal,” said Johnston, an under-20 champion at the CONCACAF and FIFA levels.  “We don’t want to have any goals against us.  We’re really disappointed that we gave one up against Australia.”

So, who would have guessed that defense would give the USA the best prospect of winning its third Women's World Cup and first in 16 years?

“If you don’t give up any goals, I think you have a hell of a chance,” Ellis finished.