There will be a fascinating star-spangled undertone to Saturday's highly anticipated Revierderby between Borussia Dortmund and Schalke, as childhood friends Christian Pulisic and Weston McKennie meet in a competitive fixture for the very first time.

Pulisic and McKennie met at the age of 13, when both playing for the US national youth teams. Little could they have dreamed, at the time, that they would go on to become two of the Bundesliga's hottest imports, and even find themselves on opposing sides of its biggest rivalry.

The two sides come into the blockbuster fixture on contrasting runs of form, with Schalke flying up to second with four wins and a draw over the last five games, while Dortmund have struggled over the same period, picking up just one point in that time.

Watch: Pulisic and McKennie gear up for the Revierderby

"The momentum that we have going into this game is really big," says McKennie, who has made eight Bundesliga appearances this season. And while Christian Pulisic can't hide from reality, optimism is ripe within him. "It's tough to argue, our form is not good right now," says Pulisic, knowing that Saturday is the perfect time to change that.

"We need to step it up and we have the perfect chance to do that this weekend," Pulisic announced.

Pulisic joined Dortmund's youth system in 2015, and set about lighting up the Bundesliga a year later when he was promoted to the first-team squad. Who was this 17-year-old kid, playing with a maturity beyond his years and breaking records for fun at one of the biggest clubs in Europe?

America soon found out. Pulisic was drafted into the USMNT squad by then coach Jürgen Klinsmann and did just about everything he could to get his country to the 2018 FIFA World Cup, scoring or setting up 12 of their 17 goals in qualifying. His remarkable efforts proved to be in vain, though, as a shock defeat in Trinidad and Tobago robbed him of the chance to shine in Russia next summer.

While they are only three weeks apart in age, McKennie has been a slightly later bloomer than his younger friend, only joining the Schalke first team in May and making his senior USMNT debut in a friendly draw with Portugal earlier this month. It took the 19-year-old all of 21 minutes to open his account for the Stars and Stripes against the European champions.

"When the national anthem was going I was smiling a little bit, because I was thinking in my head, 'I finally got to this point'," McKennie explained to ussoccer.com. "I'm blessed that I was able to score a goal today on my debut, and I look forward to many more. This group is full of energy. We just want to turn the page and show the US what the future holds."

One thing beginning to look ever more likely is that the future of the American national team will be a side built around the talents of midfield duo McKennie and Pulisic. However, with no major tournaments on the horizon until at least 2019, it is domestic matters that will take centre stage for the time being - starting with the all-important Revierderby on Saturday.

Watch: Pulisic and McKennie face-off in a US Sports Quiz!

Saturday's clash at the Signal Iduna Park would be the perfect moment for Dortmund to finally get back to winning ways. Since the start of October they have managed just a single victory in nine matches in all competitions, with two draws against APOEL and defeat to Tottenham Hotspur ending their chances of reaching the UEFA Champions League knockout stage.

McKennie and Schalke have other ideas, however. After making a couple of appearances from the bench at the start of the season, the 19-year-old was handed his first Bundesliga start against champions Bayern Munich and has gradually worked his way into Domenico Tedesco's starting eleven. He played the full 90 minutes in Schalke's last two outings, wins over Freiburg and Hamburg, and has every chance of facing Dortmund from the outset this weekend.  

Watch: Five things on the Revierderby

"I'm really looking forward to the derby against my so-called 'friend' Christian," McKennie joked. "The momentum that we have going into this game is really big, and it's a good feeling being in front of them. I think the fans are enjoying it too!"

Indeed, the Royal Blues find themselves above their Black-and-Yellow rivals in the Bundesliga table for the first time in two and a half years, since the final day of the 2014/15 season.  If they can claim their first Revierderby win at the Signal Iduna Park since October 2012 this weekend, they will move six points clear of BVB and remain within touching distance of leaders Bayern.

Whatever the outcome, there promises to be a ferocious red, white and blue midfield battle on Saturday, as Pulisic and McKennie put their friendship aside for 90 minutes and go head-to-head in their first ever competitive meeting. The Bundesliga's American whizz kids will be determined to put an end to a run of three Revierderby stalemates, and hand their passionate fans some long-awaited local bragging rights. 

Andy Smith

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