David de Gea saved two spot-kicks as Manchester United beat Real Madrid 2-1 on penalties in the International Champions Cup, after the match ended 1-1 at Levi's Stadium on Sunday.
Casemiro, who scored from the spot in the second half to cancel out Jesse Lingard's opener, missed the crucial penalty after De Gea kept out efforts from Mateo Kovacic and Oscar Rodriguez.
Only three of the 10 spot-kicks taken in the shootout were successful, with Daley Blind and Henrikh Mkhitaryan the scorers for Jose Mourinho's side.
Marcus Rashford and Lingard kept their places from the 2-0 victory over Manchester City as Mourinho made nine changes to face the Champions League winners.
Lingard looked bright and drew a smart stop from Keylor Navas with the game's first meaningful attempt on eight minutes.
The England international went close again moments before his goal, firing just wide from 22 yards.
When the opener came, it was courtesy of a fantastic assist by Anthony Martial. The Frenchman danced past three Real players and teed up Lingard, who swept home from close range.
Zinedine Zidane changed his entire team at the break, while Mourinho made eight substitutions, bringing on Romelu Lukaku and Paul Pogba.
One of those introductions was Ander Herrera but the Spaniard lasted just six minutes before being forced off injured.
Real were on level terms when Victor Lindelof wiped out summer signing Theo Hernandez in the penalty area, with Casemiro on hand to dispatch the spot-kick.
Both teams struggled to create in hot conditions but the best chance for a winner fell to Marouane Fellaini, who miscued over on the volley from seven yards.
In the penalty shoot-out, the first four takers all failed - Martial and Scott McTominay for United and Kovacic and Oscar for Real - before Mkhitaryan put United in front, only for Kiko Casilla to then save from Lindelof.
But Hernandez dragged his effort wide for Real, Blind sent Casilla the wrong way and Casemiro struck the crossbar to seal victory for United.
Man of the match: David de Gea
The Spain goalkeeper was alert to keep out a cheeky free-kick from Luis Miguel Quezada before stepping up in the shootout.
United travel coast to coast as they head to Maryland next to face Barcelona at FedEx Field on Wednesday.
Real will stay in California as they face Manchester City in Los Angeles on Thursday.