SANTA CLARA -- Pro Bowl defensive lineman Justin Smith's partially torn left triceps tendon likely will force him to sit out a second straight game. However, he appears intent on returning in time for the 49ers' first playoff game.
Smith is doubtful for Sunday's game against the Arizona Cardinals, but he told the Sacramento Bee on Friday that he will be ready to play if the 49ers wind up in a wild-card game next weekend.
Smith suffered his injury against the New England Patriots on Dec. 16 and missed the remainder of that game, as well as the game against the Seattle Seahawks last Sunday.
Coach Jim Harbaugh said there's a "higher risk" of Smith exacerbating his injury if he plays Sunday.
Then again, "It's something that he'll have to have surgically repaired at the end of the season either way," Harbaugh said.
Davis said he is feeling better five days after being waylaid by Seahawks safety Kam Chancellor and that he intends to play. Harbaugh said Davis' availability is at the discretion of team doctors.
He'll be examined Saturday to determine whether he's well enough for contact. Davis has played in 90 straight games.
"There's a lot on the line," Davis said, acknowledging that it might be wise to sit out. "We want to win this game, no matter what. We've got to win this game. So, my mind is just focused on trying to help my teammates win this game any way I can."
Linebacker Clark Haggans (shoulder) and defensive tackle/fullback Will Tukuafu (neck) also are questionable. Thirteen others are probable.
The three offensive tackles selected to the NFC squad -- Joe Staley of the 49ers, Russell Okung (Seahawks) and Trent Williams (Redskins) -- all play on the left side.
"That's how the game is right now," Davis said. "If I stay at right tackle, I'll change it. I have to because this year, you saw what happened."
Left guard Mike Iupati, drafted six spots after Davis by the 49ers in the first round in 2010, made his first Pro Bowl. Iupati said he and his teammates expected Davis to be selected.
"We were all shocked," Iupati said. "He's had a great year. That definitely caught us by surprise. I guess they think all the athletic guys play on the left side, but the guys on the right side have to block the elite pass rushers, too."
The 49ers signed defensive lineman Tony Jerod-Eddie to the 53-man roster from their practice squad to take the spot created by the Manningham transaction.
Jerod-Eddie, an undrafted free agent out of Texas A&M, signed a three-year contract as part of his promotion.
Manningham appeared in 12 games for the 49ers this season, his first after signing with them in March, and caught 42 passes for 449 yards and one touchdown.
Jerod-Eddie adds depth to a defensive line that played without Smith and key reserve Demarcus Dobbs in recent games. Dobbs is out for the season.
The 49ers also considered promoting a wide receiver from their practice squad to replace Manningham, those options being Chad Hall or Ricardo Lockette. However, rookie top draft pick A.J. Jenkins is expected to suit up for the third time this season.
"I'll appeal it because you can see it was just through the whistle," Davis said. "It was legal. I'll appeal it, and it should get taken care of."
Cornerbacks Chris Culliver and Tramaine Brock weren't fined for their unnecessary-roughness penalties in the same game.
Meanwhile, the league didn't fine Chancellor for his vicious hit on Vernon Davis that resulted in Davis' concussion. Same goes for Seahawks linebacker Leroy Hill, who wasn't fined for a knee-level tackle that caused Manningham's injuries.
"It was pretty brutal," Davis said of Chancellor's hit. "Brutal. I don't think it was legal, no. I saw it on the news, but I didn't really go in and look at it. I didn't want to see it."
"It's been pretty much a one-way street," Harbaugh said. "I've been the one doing the learning. He's been great. We probably talk not every week but every other week. He follows our team closely, and he's somebody that I routinely ask for advice."