A second-half strike against Stuttgart made it two goals in two games for the German-born U.S. international.
Takashi Usami opened the scoring for Hoffenheim in just the fifth minute, and Joselu doubled the lead soon after halftime. Johnson put himself on the score sheet in the 58th minute.
The tally marks the second time in two games Johnson has found the net, after his equalizing strike against Hannover 96 on Sunday, a match in which fellow German-American Danny Williams also scored.
Johnson, who began his career at 1860 Munich and had a spell at Wolfsburg before signing with Hoffenheim in 2011, received his first U.S. national team cap in November 2011, coming on as a substitute in a 1-0 friendly loss to France. He has made nine total appearances for the U.S.
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