Summer signing N'Golo Kante made his first appearance for Chelsea as two goals from Oscar saw the Premier League side beat AC Milan 3-1 in Minneapolis.
The International Champions Cup friendly was the first sporting event to be held at the new $1.1bn (£830m) home of NFL side Minnesota Vikings.
Bertrand Traore headed the opener for Chelsea before a Giacomo Bonaventura free-kick drew the Italian club level.
Brazil midfielder Oscar's brace sealed it for Antonio Conte's side.
Kante, who left Premier League champions Leicester for a fee in the region of £30m, came on as a second-half substitute.
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