About 20 men, one waving a Palestinian flag, ran on the field in the 87th minute of Roma's 1-0 win over Real Madrid at the Cotton Bowl on Tuesday.
Players and team officials waited as the intruders were rounded up and removed from the scene. Some players stretched while others just stood with hands on hips as the fans ran past looking for acknowledgement.
Roma veteran Francesco Totti scored the only goal on a cross from the right by Alessandro Florenzi in the 58th minute.
Roma nearly made it 2-0 about a minute later, but Adem Ljajic had a close miss. Real Madrid's Isco shot just right of the goal in the 60th minute.
Roma's next game in the International Champions Cup friendly tournament is against Italian rival Internazionale on Saturday, when Real Madrid will play Manchester United.