The 2022 runners-up, France, will be strong favourites to beat Sweden when they meet on Tuesday in New Jersey.
Speaking at Sweden's training base in Dallas, Arsenal striker Gyokeres made no attempt to play down the scale of the task facing his team.
"We will have to be at our best, we have to do our defensive organisation almost perfect and then of course to take the chances we will get," he said.
Sweden squeezed into the knockouts, thrashing Tunisia 5-1 and then losing to the Netherlands by the same scoreline.
Graham Potter's side, who needed to go through the playoffs to reach North America, edged through the group with a 1-1 draw against Japan.

Despite an erratic campaign, Gyokeres said: "We have our confidence. I think we have to believe in ourselves.
"We've seen in a lot of games this tournament that you can win games (as underdogs). You can do well even though you play against the best teams.
"Of course we might be the underdogs, but we still believe in ourselves."
Gyokeres will come directly up against Arsenal team-mate William Saliba, something he is relishing.
Asked by AFP about the prospect of that, he said: "I'm looking forward to see him and to play against him, it's gonna be fun."
France made a statement in the group phase to show why they are one of the favourites, winning all three matches with Kylian Mbappe and Ousmane Dembele both scoring four times so far.
FIFA World Cup 2026
The 2026 World Cup is taking place from June 11th to July 19th in the United States, Canada and Mexico. The tournament features 48 national teams and is played at 16 modern stadiums.
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