England's 2-0 defeat by Australia at a rain-lashed Brentford Community Stadium ended their 30-game unbeaten run since Dutchwoman Wiegman took over in 2021.
Remarkably, they enjoyed 70% possession of the ball but struggled to make much from it as Australia packed the midfield and left no space for England's creative players.
Australia then picked their moments to counter-attack in clinical fashion as England ran out of ideas.
It is likely to become the blueprint for stopping England's women who will not be able to call on Euro 2022 Golden Boot winner Beth Mead (27) in Australia because of injury.
"We play against some opponents now that drop a little deeper, are really tight," Wiegman said. "So we have to find solutions and find a way to create more to score goals.
"There's 100 days to go and everyone's really excited to go to Australia and this is just a very big learning moment for us that we need to get to a higher level to win these games."
England captain Leah Williamson (26) said they would turn the defeat into a positive.
"Sometimes you have to take blessings in disguise and I think maybe that's not the worst thing that could've happened to us," she told Sky Sports.
"We wanted to learn this whole time, we wanted to be pushed to our limits and we need to take it up a new level."
England's next match will be their World Cup opener against Haiti on July 22.
