Martina Voss-Tecklenburg has challenged her Germany players to continue improving after it became the first side to book its place in the last eight of the Women's World Cup with a 3-0 win over Nigeria on Saturday.

Germany was two goals in front before half-time and added a third eight minutes from the end to reach the quarter-finals for an eighth time in a row.

Alexandra Popp marked her 100th international appearance with a close-range header - allowed to stand after a VAR check for offside against team-mate Svenja Huth - and Sara Daebritz tucked away a contentious penalty to make it three goals in as many matches.

READ : Women's World Cup: Germany vs Nigeria, as it happened

And after struggling to create many clear-cut opportunities after the interval, Lea Schueller scored with a clinical finish late on in Grenoble to maintain Germany's winning momentum.

Voss-Tecklenburg's side will now take on either Sweden or Canada for a place in the semis and the German coach is glad to have a full week's rest.

"Coaches are never 100 per cent happy but that was a great performance and it's fantastic to be in the quarter-finals," she said.

"We've played four very tough matches in very different conditions, with the heat tough today, and we've dealt with all that very well.

READ : Women's World Cup: VAR talk dominates as Germany reaches quarterfinal

"I'm very happy that we now have one week to relax and prepare for the quarter-finals. Part of that will be working on improving our performance in certain phases of the match, gaining more ground, becoming more confident and not allowing ourselves to get frustrated by small details."

Nigeria wasted a good opportunity early in the second half and then gifted Germany its third goal when an underhit back-pass was latched on to by Schueller.

Coach Thomas Dennerby admits Nigeria still has plenty to learn but is pleased with its recent progress, having reached the knockout rounds of the Women's World Cup for just a second time.

"I think we showed the whole world that Nigeria have a team that has improved a lot," he said. "Of course you're not satisfied to go out but you also have to recognise where we came from - and we're just not ready yet. 

"It’s important to play high-level teams like Germany because the players can see that even the smallest mistakes get punished. 

"But the second half was really good and now we just need to focus on improving and using all the FIFA dates to play matches, because we have some really talented players back in Nigeria."