The American then took the ball off Mario Gotze and duly dispatched from the spot to draw Dortmund level and give the United States crowd a goal from one of their own.
After missing out on the World Cup with England - less than a year after Gareth Southgate suggested he was one of the national team's key players - this is a huge 12 months for Adam Lallana.
Dortmund, meanwhile, have now won both of their matches in this year's International Champions Cup and would finish the pre-season tournament with a 100% record if they also beat Benfica in Pennsylvania next week.
Casillas is now playing his club football for Porto after spending the majority of his career in goal for Real Madrid.
Speaking before the game, Matip admitted he had yet to return to full fitness and was hoping it would present another step to recovery.
At Leipzig, he played as a winger, that's for sure not his best position but he can play it because he has the speed for it, he has the football intelligence for it.
United States indicts Russian intel officers ahead of Trump-Putin meet
Rosenstein said the Americans who were corresponding with the GRU officers were unaware they were Russian operatives. Now, the indictment has confirmed the earlier reports of the solo hacker being Russian intelligence agent.
While a third supporter questioned if he was still having health issues.
Sheyi Ojo - 5: Showed off his blistering pace but is missing that close control to become a really deadly goal scorer, missed a guilt edge chance set up by Sturridge when he really should have done better to put Liverpool 2-0 up.
Unlike their opponents on Sunday, Dortmund do have until the end of August to finalise all their transfer dealings and a striker - possibly even Batshuayi on a permanent deal - must be number one on Lucien Favre's list.
Nat Phillips - 6: Composed presence at the back, cutting out some risky balls with his head, was not really at fault for any of the Dortmund goals but maybe could have stepped in a bit more when he saw the danger.
The German goalkeeper lost a lot of trust when he made two costly errors in the Champions League final.
And, despite Klopp's side dominating much of the remainder of the match, they were undone late on when Pulisic struck a second and Jacob Bruun Larsen sealed the result.