Dwayne Harris muffed a punt after the Cowboys defense forced a three-and-out to start the game and later the special teams unit allowed a 28-yard kickoff return.
"Dwayne Harris is trying to hold it, the guy comes back in from the back," coach Jason Garrett said of Harris' miscue.
In the last two weeks, the Cowboys have had two muffed punts, a blocked field goal and allowed at least two kick returns of more than 25 yards.
Garrett said after playing the Raiders he was pleased with how the younger players reacted to the speed of the game on special teams but still wanted execution. The players ran well on all the special teams units, but it should be somewhat concerning the special teams units have gone consecutive weeks with turnovers.
Harris appears safe as the punt returner, but the Cowboys had receiver Miles Austin and B.W. Webb fielding punts in practice. Webb has also fielded punts in preseason games but Austin is just doing so in case something happens to Harris from an injury standpoint.