Mario Gotze, Borussia Dortmund Beat Manchester City in 2018 ICC

Mario Gotze netted a first-half penalty to lead Borussia Dortmund to a 1-0 victory over Manchester City in the opening match of the 2018 International Champions Cup on Friday at Soldier Field in Chicago.

Gotze stepped up to the spot in the 28th minute after American teenager Christian Pulisic earned the penalty. He converted the attempt off the outreached hand of City goalkeeper Claudio Bravo. It was the spotlight moment of a solid preseason performance for the German midfielder.

Meanwhile, Riyad Mahrez made his debut for the reigning Premier League champions and provided a couple of sparks for an otherwise lackluster City attack that featured a lot of youthful contributors.

City acquired Mahrez on a £60 million transfer from Leicester City earlier this month. The Algerian international was one of the driving forces behind the Foxes' miracle run to the 2015-16 Premier League championship, and he'll attempt to help his new club secure back-to-back titles.

The 27-year-old winger navigated a mostly uneventful first match with the Sky Blues. He controlled the pace of play well when on the ball and showcased his playmaking ability, highlighted by a well-placed free kick that forced Dortmund goalkeeper Marwin Hitz to make a save right before the halftime whistle.

Mahrez was subbed out after 72 minutes, but his impact will be expected to steadily increase as the new term moves closer. He's aiming high after completing the long-rumored move.

"City have ambition to go further than the Champions League quarter-finals like they did last season," he told reporters in his introductory press conference. "I made the decision to come here because I want to be part of that. The Champions League is for big clubs. They're a big club, they have everything to try to win it."

Meanwhile, Pulisic is facing a key season for Dortmund. While the 19-year-old American is also viewed as the centerpiece of the United States national team, he's coming off an up-and-down campaign for BVB with four goals and five assists in 32 Bundesliga appearances.

The talented midfielder must work to become a more consistent attacking threat. He started the preseason well in that regard as he was a constant presence in the final third and drew the foul in the box that led to Gotze's opening goal from the spot.

All told, it was a pretty standard preseason fixture with each manager testing a variety of players and utilizing ample substitutions. It was far from a clinical performance by either side with 23 combined fouls compared to six shots on target.

Both clubs will return to action next week against Liverpool as their U.S. tours continue. Dortmund will take on the Reds at Bank of America Stadium in Charlotte on Sunday, while Manchester City are set to battle their EPL counterparts Wednesday at MetLife Stadium in New Jersey.