The USA left back sliced his team's deficit in half with his third goal of the season, but Hoffenheim's comeback came up short.
With Hoffenheim trailing 2-0 in the 59th minute, Johnson cut to his right foot inside the area and rifled about a 12-yard shot inside the far post and past the outstretched arms of diving Leverkusen goalkeeper Bernd Leno to slice the club's deficit in half.
Hoffenheim could not complete the comeback, though, and was dealt its second straight loss. The club dropped to 3-7-3 and 16th place in the Bundesliga -- one point behind Timmy Chandler's FC Nurnberg -- sitting in the spot reserved for the relegation playoff at season's end.
Fellow U.S. international Danny Williams was an unused substitute in the match.
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