The Cardinals are being uncharacteristically loose with the ball, and the Rams are making them pay for it.
Rams quarterback Nick Foles just Stedman Bailey in the corner of the end zone for a 17-9 lead over the Cardinals.
The score came after they forced a Larry Fitzgerald fumble, which was the third fumble lost of the day for Arizona.
On the last one, safety Rodney McLeod put his shoulder on the ball as Fitzgerald turned upfield with a reception. Rookie David Johnson has also put it on the ground twice, which is why the Cardinals have tried to ease him into the rotation despite his skill.
The Rams scored after two of them, and are making enough plays to stay out front on the road.