As many as 11 different scenarios could unfold when the U.S. women's national team concludes the group stage of the Women's World Cup in Vancouver on Tuesday night against Nigeria (8 pm ET, broadcast on Fox, NBC Universo, Fox Sports Go).

Sweden vs. Australia will play simultaneously in Edmonton, and the results of those two games determine who finishes where in the Group D standings, and which two or three of those teams will survive and advance to knockout-stage games next week.

But for Abby Wambach and the U.S., beating their mystery-cloaked African opponents at BC Place is the simplest and most effective way to keep their world championship dreams alive.

"We have to go out No. 1 in our group," Wambach told reporters on Saturday as the USWNT transitioned from Winnipeg, site of their first two games, to Vancouver. The squad hopes to get comfortable on the Pacific Rim: The city will also host the World Cup final on Sunday, July 5.

"I think that they're [Nigeria] going to play as hard as they can," Wambach added. "They're fighting for their lives in this tournament."

Winning the group would provide the U.S. with a smoother path towards the trophy, ensuring that their next game is in western Canada - whereas the second-place finisher must travel all the way across the country to Moncton, where a dangerous Brazil side would be the likely opponent.

Wambach raised eyebrows this week when she claimed that her team's scoring, which has failed to meet their own expectations thus far, would be higher if this tournament were being played on natural grass and not synthetic turf.

While she did see a goalbound header against Sweden take a bigger bounce than it would've on grass, helping goalkeeper Hedvig Lindahl make the save, her words got a skeptical reception among observers who have heard her complaining about Canada's use of turf for more than a year, including in an ultimately unsuccessful legal action against FIFA.

With more attacking talent on their roster than head coach Jill Ellis can cram into the starting lineup, the USWNT should have no need for such excuses. And whether Wambach was speaking earnestly or simply trying to take some pressure off her teammates, her words hinted at the pressure weighing on this squad as a nation waits to be charmed like it was four years ago.

"I can understand the angst. We're more popular than we were four years ago. So people only got on board in the latter part of the [2011 World Cup]," said Wambach.

"It never goes the way you envision it going. Nothing ever does in life. That's what makes a difference between great teams and not-so-great teams. It's the teams that can adapt in all situations, to plans completely falling apart, to scouting a team and then doing something completely different."

More than half (16) of this World Cup's 24 participants get to advance to the win-or-go-home knockout stages. And with a win and a draw thus far, the U.S. is almost (but not quite) guaranteed to move on regardless of what happens. But Nigeria, a quirky team capable of both spectacular scoring and atrocious defending, needs to win this game to survive.

Coming off a drab display in Friday's 0-0 draw with Sweden, the USWNT are feeling some urgency to score goals and build rhythm before they meet elite opponents in the later rounds. Attacking recklessly could backfire, however, given the Nigerian forwards' speed and creativity.

"Super Falcons" striker Francisca Ordega will be familiar to most of the U.S. squad thanks to her recent arrival and strong start in NWSL with the Washington Spirit, where she's scored two goals and two assists in her first five matches. She and her forward partner Desire Oparanozie can cause chaos, as can free-roaming midfielder Asisat Oshoala - as Sweden found out to their dismay in last week's wide-open 3-3 draw.

"[Nigeria] give space, but they close it very, very quickly," Ellis said at her official pregame news conference.

But at the other end, goalkeeper Precious Dede looks like a weak link ripe to be targeted, especially when Wambach and the rest of the strong, physical U.S. squad crowd into her penalty box on corner kicks and free kicks. Dede will surely concede scoring chances - but the USWNT will have to prove that they're capable of putting them in the net.

"We have to be patient," Wambach said on Saturday. "We can’t force goals to happen. We have to work for them."

By Charles Boehm, who covered the USMNT and the World Cup for Gothamist last year. He has covered MLS and the American soccer scene since 2004, contributing to MLSSoccer.com, The Soccer Wire, and USSoccerPlayers.com.