Inter coach Antonio Conte claimed Borussia Dortmund feared his team following their 2-0 Champions League victory on Wednesday.
Lautaro Martinez and Antonio Candreva both scored for Inter at San Siro, where the Italian side registered their first Champions League win under Conte.
Martinez - who also had a second-half penalty saved - made it five goals in four games for Inter as he opened the scoring in the 22nd minute before Candreva sealed the Group F points with a minute of regulation remaining.
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It was Inter's first victory over German opposition since March 2011 and Conte told Sky Sport Italia: "Borussia Dortmund changed their system to five at the back, which means they were afraid of us and wanted to play by changing their approach to mirror ours.