Manchester United defeated rivals Manchester City 2-0 at the NRG Stadium in Houston, Texas thanks to goals from Romelu Lukaku and Marcus Rashford.
Lukaku's opener was his second in a red shirt, having got off the mark against Real Salt Lake on Tuesday.
For added entertainment, Chris Smalling made an unusual recovery to complete what should have been a simple pass.
In the 35th minute, the England man lost his footing while chasing a ball down with Sergio Aguero bearing down behind him.
Yet, somehow - intentionally or otherwise - the 27-year-old managed to do just enough to nod the ball back to De Gea, who showed far more composure by gently kicking the ball away from danger.
Manchester City's £50m signing Kyle Walker made his first start in the friendly, but couldn't stop United from emerging victorious in the first Manchester derby played outside of the UK (it should have happened in China last summer, but for a waterlogged pitch).
