Germany is playing like a title contender, just at the right time.

After seeing her team start the Women's World Cup with a pair of one-goal wins, Germany coach Martina Voss-Tecklenburg told her players to keep the game simple.

Germany played to its status as the world's second-ranked side and one of the top challengers hoping to dethrone the United States, routing South Africa 4-0 on Monday to top Group B with a 3-0 record. The Germans will play a third-place team in the round of 16 instead of the possibility of an immediate matchup with the Americans.

After Germany grinded out 1-0 wins over China and Spain, its offense broke out with three goals in the first half at Montpellier's Stade de la Mosson, matching its total in its previous five World Cup games combined.

"I told my players that we should keep it simple," Voss-Tecklenburg said. "The players performed very well. They showed that football can really be very simple sometimes. ... There were moments within the match when we tried to go for the more difficult solution. That's something we can work on."

Displaying a varied attack, Germany generated a constant stream of scoring opportunities and could have easily won by a bigger margin.

Melanie Leupolz opened the scoring in the 14th minute with her first goal for Germany since the 2016 Olympics. Sara Däbritz doubled the lead in the 29th minute from a goal-keeping blunder, Alexandra Popp made it 3-0 in the 40th and Lina Magull added the final goal in the 58th.

"I think we are ready for the round of 16," Däbritz said. "Our goal was to come in first, and we are really happy about that."

South Africa was winless in group play and outscored 8-1. At 49th, South Africa had the lowest ranking of the 24 teams in the tournament.

Spain finished Group B as runner-up after a 0-0 draw with China and advanced to the knockout stage for the first time. Spain will face the winner of Group F on Monday at Reims, and the United States would be the opponent with a victory or draw in its final group match against Sweden.

Two-time tournament champion Germany has not lost a match in group play since falling to Sweden in 1995.

"Germany has won tournaments that it started out with difficulties," Voss-Tecklenburg said. "It would be great to have the same this time. All the matches will be challenges, and I hope we will be able to meet them all."

Germany didn't miss the playmaking of Dzsenifer Marozsan, who broke a toe in its opener. Voss-Tecklenburg said she couldn't guarantee the Lyon midfielder will be ready for the round of 16.

Leupolz put Germany ahead when she was left all alone on the edge of the 6-yard box to deftly nod a corner kick into the far corner of the net.

Däbritz made it 2-0 after a mistake by goalkeeper Andile Dlamini, who turned what appeared to be a poor German pass into a perfect assist.

Left back Verena Schweers's cross looked like an easy grab for Dlamini, only for Dlamini to parry the ball right into the path of Däbritz, who got her second goal of the tournament.

"We conceded poorly from a set piece and a second goal, as well, and were on our back foot from there," South Africa coach Desiree Ellis said.

Germany boosted the lead to 3-0 with pure power. Popp, the team captain, jumped over her marker to drive home a header.

Magull got the fourth goal when she rushed in to finish off a save by Dlamini, who did well to push a header by Marina Hegering off the post, only to see the ball bounce across the open goalmouth.

Only Dlamini's sharp reflexes saved South Africa from a greater defeat.

"We always knew it would be a challenge," Ellis said. "We are happy with the performance but not the result."