U.S. midfielder Weston McKennie had to be carried off the field Saturday after taking a kick to his left leg in the second half of Schalke’s 2-0 loss to German champions Bayern Munich.

The incident occurred in the 51st minute of the Bundesliga match in Gelsenkirchen. McKennie darted in front of Bayern’s James Rodriguez and won the ball, only to catch Rodriguez’s attempted clearance square on the shin. The foul earned Schalke, then trailing 1-0 on Rodriguez’s first-half goal, a dangerous free kick. But McKennie — who was in obvious pain — was removed from the match and replaced by Nabil Bentaleb before it could be taken.

The chance was squandered in the end, and Bayern striker Robert Lewandowski doubled the visitors’ advantage from the penalty spot later on to put the game away.

McKennie missed last week’s 2-1 loss to Borussia Monchengladbach because of an issue with the same leg; the 20-year-old suffered a bruised left knee playing for the United States against Mexico on Sept. 11. But he was able to return to Schalke’s starting lineup for Tuesday’s Champions League group stage tilt versus Porto, with the Texan notching an assist in the 1-1 tie.

While there was no immediate update on McKennie’s injury post-match, this latest ailment could put McKennie in doubt not only for Schalke’s two Bundesliga matches next week, but also the U.S. men’s national team’s friendlies against Peru and Rodriguez’s Colombia next month.

Doug McIntyre covers soccer for Yahoo Sports. Follow him on Twitter @ByDougMcIntyre.

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