Although the idea of overloading the midfield makes sense, dropping one of the team’s fastest and most agile players into an unnatural position is puzzling, especially when the midfield of Tillman, Quinn Sullivan and Brendan Aaronson doesn’t offer much in the way of pace.

Patrick Agyemang’s 75th-minute goal secured a 2-1 victory in Arlington, Texas. The quarterfinals are next.