However it’s the two other Scots teenagers in her team, St Regulus club member Caithness and Elie and Earlsferry’s Sally Watson, whom McKenna believes will prove to be the key advantage on her team.

Krystle has grown up as a golfer on the St Andrews links and won the St Rule Trophy last year before heading off to the University of Georgia, while Sally, a pupil at the David Leadbetter Academy in Florida, knows the links well and is the only player on either side to have played it at the maximum length which will be used for this weekend’s matches, when she played all four rounds of the Ricoh Women's Open last year.

While Caithness yesterday looked as chilled as the US team wrapped in a muffler—she too flew in from the NCAA women’s tournament in New Mexico where high winds caused a cancellation of one round and temperatures dipped to four degrees—McKenna reckons the Anstruther player could be her key.

“Having Krystle and Sally, and all their experience around here, will be a key advantage for us,” said the Irishwoman. “Just having them talk about the the way they play holes is helpful and they also have an idea of pin placements because on this course above all others you play the hole differently dependent on the pins.

“There are little things, things you wouldn’t even think of if you didn’t have experience of this course and the way it plays, that they can tell us which could be crucial.”

The only concern over three days of practice so far has been Booth being slightly under the weather, and the weather itself yesterday which made conditions difficult.

“Carly has a slight throat infection but we’re on top of it now,” said the captain.

“We pulled her from yesterday’s practice and she’ll be grand.

“You know, she’s had so much to deal with in the last few weeks with exams on top of this that it probably did her good to have a couple of days’ break.”

McKenna did pull her team off the links yesterday in caution against the conditions.

“It’s supposed to be better at the weekend and the conditions didn’t improve,” she explained. “You don’t do yourself any good fighting the wind like that, and we’ve done enough work over the last few days so that we can play the course depending on whatever wind we get.”

The skipper is quietly confident that her team can win, even if they lack experience, England’s Liz Bennett being the elder stateswoman of the team at 25 and everyone else 20 or under.

“I believe we will win,” she said. “We’re under no illusions that it’s going to be a cakewalk just because it’s St Andrews, and this is a good American team, but we are quietly confident.

“I’m not concerned my team are so young. To be honest, when I was 15 I hadn’t ever left Dublin, yet these girls have travelled around the world on their own, played in Junior Ryder Cups, had much more experience than I’ve ever had and are so much more confident.

“They’ve all played in America, and they know they’re as good as the Americans. Some of our team have played big events in front of big crowds like the British Women’s Open, so I’m not concerned about their experience.”

Carole Semple Thompson, the veteran US captain, believes she has one of the strongest teams the Americans have produced in recent years but thinks the matches are too close to call.

“We’ve had six round of practice and this team is so good they will adapt to the different kind of conditions we’ve had here, both in terms of the course and the weather,” she said.

“I don’t know why we’ve dominated the matches in recent times, because I think the teams have roughly been the same in terms of talent, and I think the same is true of this year.”

The teams will have one more morning of practice today before this evening’s opening ceremony at 6pm in front of the R&A clubhouse.