The Rams scored easily on their first possession, going 75 yards in seven plays with Malcolm Brown scoring on a 1-yard run. They were on their way to a second score, converting a fourth down, before stalling at the Dallas 11.
But Rams rookie kicker Samuel Sloman missed his first career kick, a chip-shot 29-yarder that hit the left upright.
The Cowboys hired former Rams special teams coordinator John Fassel in the offseason, and kicker Greg Zuerlein followed him to Dallas.
The Rams have dominated Dallas every which way they can. The Cowboys ran six plays on their opening possession, gaining 23 yards before an Aaron Donald sack of Dak Prescott. That left Dallas with a third-and-16, and Prescott threw incomplete to force a punt.