The meticulous Canadian coach believes that some of his players, in advance of Saturday's opening 1-0 win over China, were allowing too much "into their world, their mind."
"We've put some new strategies in place," Herdman told his news conference ahead of the New Zealand game. "So even though they've had plans in place (to avoid distractions), the temptation to spend that extra little bit of time with family and worrying about a ticket for somebody and the little temptation to check Twitter and someone's said something derogatory about you three hours before the game, which happens.
"Those little details all make a difference. And there were certainly some players that have let clutter in that they didn't need to."
Herdman, whose staff includes a "mental team," said such distractions were one factor in Canada's uneven opening performance Saturday. He also cited the heat, saying his players had paid the price for trying to "blitz" China in the opening minutes.
Herdman said his players strayed from the game plan as fatigue set in. "In the heat they just needed to be more patient," he said.
Thursday's conditions should be more temperate, with a 7 p.m. local time start instead of 4 p.m.
Away from the pitch, all four Group A teams are staying in the same Edmonton hotel, away from downtown.
There is not much close by but the Canadian women have their own lounge at the hotel, complete with puzzles, TV and a PlayStation video game console.
They are also rental cars available to use and time allocated for family and friends. The team makes daily expeditions to a local coffee shop.
"We have a good balance between having meetings, having treatment, getting family and friends time," said defender Marie-Eve Nault. "I think (Herdman) is really cognizant that we need a balance. Because if we're always only surrounded by our teammates, closed down in a hotel it's like we can't get out of our bubble."
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