ARLINGTON (August 29, 2012) -- Orie Lemon returned an interception 26 yards for a touchdown, No. 3 running back Phillip Tanner had a 1-yard score and the Dallas Cowboys finished their preseason with a 30-13 victory over the Miami Dolphins on Wednesday night.

A week before playing in the NFL's kickoff game against the defending Super Bowl champion New York Giants, the Cowboys kept quarterback Tony Romo and most of their front-line starters standing on the sideline.

Rookie quarterback Ryan Tannehill, the first-round draft pick from Texas A&M already tabbed Miami's starter, was 5-of-7 passing for 35 yards playing the first two series. The Dolphins led 3-0 when he was done.

Miami finished its preseason winless under new coach Joe Philbin. The season opener is Sept. 9 at Houston.