Task: Question Understanding
Input (English): Passage: A rejuvenated Nick Foles got his starting job back after being benched in favor of Case Keenum, who suffered a concussion after last week's loss in Baltimore. However, Foles' return was marred as he struggled to find open receivers and was picked off three times by the Bengals ranked defense. He also took hits throughout the game and he was sacked a few times. The only Rams score was a 5-yard run by Tavon Austin on a reverse play in the second quarter. St. Louis' defense was not a factor all game as they struggled to stop the high-powered Bengals offense led by quarterback Andy Dalton, and receivers A. J. Green, and Tyler Eifert, (the latter left the game with a stinger) who is leading the league in touchdown catches. With the loss, the Rams extended their losing streak to 4 games, making their record 4-7.
Question: Who did Keenum suffer his concussion playing against?
Output (English): span