The Green Bay Packers are getting adding two important pieces back to their defense in advance of Saturday’s playoff game against San Francisco.

It was announced Friday afternoon that outside linebackers Za’Darius Smith and Whitney Mercilus had been activated from injured reserve. Defensive lineman Jack Heflin and cornerback Isaac Yiadom were released to make room for the two veterans.

Smith hasn’t played since Week 1 against New Orleans. He was placed on injured reserve shortly after due to a back injury. He underwent surgery and the chance he could return this season was in doubt. However, the two-time Pro Bowl linebacker returned to practice two weeks ago and is good to go.

The same goes for Mercilus, though he seemed to be an even longer shot to make it back than Smith. A midseason free agent addition from Houston, Mercilus tore his bicep in mid-November and was thought to be lost for the season. Instead, he fought his way back and practiced the last two weeks just like Smith.

Cutting Yiadom is also an indication that Jaire Alexander will make his return against the 49ers. The All-Pro hasn’t played since a Week 4 shoulder injury against Pittsburgh. But he has practiced throughout the last five weeks and it now appears he’s ready to step back on the field.

Heflin and Yiadom had been with the team all year. It’s possible they could return to the practice squad next week.