Marcus Peters has only been with the Baltimore Ravens for a couple of days, but he is expected to play a big role on Sunday against the Seattle Seahawks.

Earlier this week, Ravens coach John Harbaugh said Peters' playing time would be determined by how much of the defense he was able to pick up.

On Friday, Harbaugh provided an updated on Peters' progress, saying he has done a great job of getting up to speed with the defense:

“He looked good. He’s going to play. He’ll probably play a lot,” Harbaugh said at a press conference, via ProFootballTalk. “So looking forward to it. Our coaches have done a great job of getting him up to speed. He’s done a really good job of studying. We’re going out there with all of our best weapons. We’re not holding anything back.”

It's hard to imagine Peters knows most of the playbook, but he should know enough to have an impact against the Seahawks. The Ravens historically have had a really good defense, although this year that hasn't been the case. They are giving up 265.5 yards per game through the air, which is 25th in the league.

Marlon Humphrey and Brandon Carr are the other two cornerbacks who are expected to have a huge impact, with all three needing to be good to slow down a Russell Wilson-led offense.

Marcus Peters is a big boost to the defense. If the Ravens want to go on the road and win, he will need to have a big game.