Wolfsburg star and 2016 Olympic gold medalist Alexandra Popp will hit 100 caps on Saturday against Nigeria.

Now Germany's captain, and still only 28, Popp made her debut against North Korea as a substitute back in 2010, narrowly missing a headed chance to score in her first outing. The striker has since gone on to notch 47 Germany goals in 99 appearances; she says that the women's game has changed immensely during her career. 

"The depth of quality has grown. Even teams competing at their first World Cup are delivering decent performances. In general, the game has become far quicker and more technical. If you watch a nine-year-old game and compare to one of today's, it's not hard to see the differences," Popp told the German DFB football association website ahead of Saturday's last 16 game. 

Focus on young guns to date

Much of the interest in Germany during the group phase revolved around the new faces in the team, especially the teenage trio of Lena Oberdorf, Giulia Gwinn and Klara Bühl. 

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Popp, however, singles out the often-forgotten youngster playing her first major tournament for Germany, 21-year-old Lea Schüller, saying "she's more my mirror image when it comes to playing styles." 

"With the 'little ones,' you can see the same sense of ease and fearlessness I used to play with," Popp told the DFB. "In the coming years, they will have to focus on maintaining this level of performance. I wish them every success in that. I didn't always manage it very well! But it's a normal part of football: you can't always play at the exact same level."

Opponents Nigeria 'very robust, tough in the tackle'

Popp missed the German women's golden age, breaking into the team after the back-to-back World Cup wins of 2003 and 2007. Injury also kept her out of the 2013 European Championship-winning German squad, making the 2016 Olympics in Rio her only major international tournament triumph. She's dreaming of the ultimate addition to her trophy cabinet. 

"That would be amazing. A World Cup, in particular, is as good as it gets. Every player dreams of that title," Popp says. 

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The first impediment to this goal, Nigeria, finished third in Group A and are distant underdogs on paper against Germany. 

"Nigeria are very robust and tough in the tackle," Popp says. "That's the case with almost all African teams. They have good, pacy attackers who know how to handle the ball. So we cannot allow them any space. At the back, on the other hand, they have their problems and aren't always well ordered. If we manage to play into these gaps and are decisive in front of goal, that will decide the match in our favor." 

Popp's coach, Martina Voss-Tecklenburg, one of the 25 other members of the German women's 100-club, is perhaps a little warier in her assessment of the next opponents. 

"We know that Nigeria are a strong side. Especially in the last game against France they showed what they're capable of. We know what a tough nut we have to crack."

Three more, probably even tougher challenges will await Voss-Tecklenburg, Popp and Germany after Nigeria if they intend to go all the way. That would take Popp to 103 appearances for Germany, and maybe the 50-goal mark too. Having netted her first of the World Cup against South Africa last time out, she's currently on 47 for her country.