Ravens cornerback Jimmy Smith had surgery Thursday morning on his injured groin, adding more pain to Baltimore's already hurting secondary.
Smith is expected to be back by the end of the season, according to Ravens Senior Vice President of Public & Community Relations Kevin Byrne.
In the meantime, Baltimore will reach deeper into its secondary and call on special teams ace Corey Graham, second-year player Chykie Brown and recently-signed veteran Chris Johnson.
"You don't expect all this to happen, but it's football," Defensive Coordinator Dean Pees said. "It's professional football. Some years you go through and you're unscathed. Some years you go through and it's not. But you have to make do with what you got."
Smith stepped in as a starter for two games after top cornerback Lardarius Webb went down with a torn anterior cruciate ligament in his knee on Oct. 14 against Dallas.
Smith was unable to play against Oakland this past Sunday because he couldn't loosen up his groin adequately. Last year's first-round pick dressed, but stayed on the sideline.
Harbaugh said the team was going to take a "hard look" at Smith's injury, and after doing so determined surgery was the best course of action.
Smith had the successful surgery in Philadelphia.
With Smith sidelined, Graham started outside and Brown saw 49 of 77 snaps against the Raiders.
Pees said he thought they played "OK," adding that they made some plays and others that they didn't. But he also said he has a lot of confidence in them.
"I think both of them are improving every day," Pees said. "We need to do a good job of putting them in the right spots."
Graham has mostly played more inside during his NFL career. He said there's not that much different sliding outside and that he's "very comfortable" with the Ravens defense at this point of the season.
"It's big for us, but other guys got to step up," Graham said. "You just have to go up there and make plays and find a way to get it done."
Baltimore also signed nine-year veteran Chris Johnson, who does not yet know how big of a role he would have in the secondary.
Pees said they will try to get Johnson ready to play as fast as possible, but "probably nobody" could get the team's schemes down in a short amount of time to be ready for the Steelers.
Johnson said he's just part of the puzzle, but is confident in his skills.
"I have knowledge of the game and speed," Johnson said. "There are really no guys that can run away from me in this league."