Dallas (ankle) has been ruled out for Sunday's game against the Rams, Curtis Crabtree of Sports Radio 950 KJR Seattle reports.
The 22-year-old sustained a Grade 3 ankle sprain during last week's win over Washington, so it's no surprise to see him ruled out this weekend. Dallas may also be sidelined for the final game of the regular season next week. Rashaad Penny should continue to work as Seattle's No. 3 running back down the stretch.