Trent Williams is active for Niners along with Keenan Allen as receiver faces Cowboys again

ARLINGTON, Texas — Left tackle Trent Williams is active for the San Francisco 49ers along with receiver Keenan Allen, who is set to face the Dallas Cowboys for the second week in a row Sunday.

Williams injured his shoulder in practice during the week, and the 12-time Pro Bowler had been listed as questionable. Allen joined the Niners in a trade with Indianapolis on deadline day Tuesday. He had four catches for 26 yards in the Colts' 27-23 loss to the Cowboys.

Receiver George Pickens and cornerback Joey Porter Jr. are set to return for Dallas after missing last week's game against the Colts.

It was the first time Pickens has been sidelined this season after dealing recently with shoulder and hamstring issues. He has been limited to 33 catches for 533 yards and two touchdowns a year after setting career highs in all three categories.

Porter has missed two of six games since joining the Cowboys in a trade with Pittsburgh. He was a late scratch with an illness four days after making his Dallas debut, then missed last week with ankle and foot issues.

Allen joins the 49ers just as fellow receiver Deebo Samuel is set to return after missing three games with a hamstring injury. Mike Evans had already been ruled out for a third straight game with Achilles tendinitis.

Cornerbacks Deommodore Lenoir (foot) and Renardo Green (back) are active after being listed as questionable by the 49ers. Both missed practice Wednesday and Thursday and were limited Friday after getting hurt last week against Las Vegas.

Linebacker Dre Greenlaw also is active. He also was listed as questionable after hurting his knee in practice Thursday.