Dallas backup safety Jakar Hamilton has been suspended for the first four games for violating the league's policy on substance abuse.
The league announced the ban Thursday. The second-year player will be eligible for the final preseason game against Denver on Thursday night.
Hamilton is the second Cowboys defensive back to get banned the first four games. Starting cornerback Orlando Scandrick was suspended for violating the league's policy on performance-enhancing drugs.
Undrafted out of South Carolina State, Hamilton played in three games for Dallas as a rookie. He had one tackle.