Manchester United defeated European champions Real Madrid 3-1 in front of a record US crowd of 109,318 in Michigan.
Two goals from Ashley Young and one from Javier Hernandez secured new United manager Louis van Gaal his fourth win of the US summer tour.
Gareth Bale's penalty was all Real could muster in reply, even after the second-half introduction of former United star Cristiano Ronaldo.
United now face Liverpool in Monday's International Champions Cup final.
United will now meet their great English rivals, who qualified for the final after Manchester City lost 5-4 on penalties to Olympiakos following a 2-2 draw in Minneapolis, in Miami.
Real's starting line-up at the Michigan Stadium in Ann Arbor was missing not only Ronaldo but also new signings Toni Kroos and James Rodriguez.
But the likes of Bale, Luka Modric and Xabi Alonso were on show in front of the largest ever attendance for a football match in the United States.
Young opened the scoring after 21 minutes but Carlo Ancelotti's Real were level six minutes later when Michael Keane climbed on Bale in the area and the Wales international tucked away the resulting spot-kick.
United regained the lead on 37 minutes when Young's cross drifted over the head of Iker Casillas.
Ronaldo's introduction against his former team with 17 minutes remaining grabbed the attention of the huge crowd, but United sealed victory moments later as Hernandez made it three.
The previous record attendance for a football match in the United States was 101,799 for the 1984 Olympic final, when France beat Brazil 2-0 at the Rose Bowl in California.
Manchester United: De Gea, M Keane, Jones, Evans (Blackett 46), Valencia (Lingard 62), Herrera (Cleverley 46), Fletcher, Young (Shaw 46); Mata (Kagawa 62), Rooney (Hernandez 62), Welbeck (Zaha 41).
Real Madrid: Casillas; Ramos, Pepe, Nacho, Arbeloa (Ronaldo 74), Illarmendi, Alonso (De Tomas 56), Carvajal, Modric, Bale, Isco.