In the 30th minute of the match against Monchengladbach, Giovanni Reyna of the United States left the field with an apparent injury.
After just returning from a hamstring injury that kept him out six months, Reyna was replaced by Julian Brandt as the team went on to destroy Gladbach by a final score of 6-0.
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The 19-year-old injured his right hamstring in the World Cup qualification match between the U.S. and El Salvadoran on Sept. 2, and had played three times for the club since returning.
The US will play Mexico on March 24 in its final World Cup qualification match, with the Americans in second place with 21 points and ahead of El Tri on goal difference.
Following Sunday's injury, his availability for the March qualification for the World Cup will be in doubt, and he has not featured for the U.S. since the Sept. 2 injury.