SANTA CLARA -- Ray McDonald has a right biceps tear that will likely require offseason surgery, but the 49ers defensive end said Tuesday that he expects to play against the Arizona Cardinals on Sunday.
"All my strength is functional, so I'll be able to play with it," McDonald said. "It should be fine. It just looks kind of funny, and I have to stay on top of my strength with it."
McDonald isn't sure how he will be impacted by the tear over the duration of the season, but he's hoping for the best.
"It's too early to tell," he said. "I'll know more as the week goes on when I start training, trying to lift on it and seeing what I can do with it."
McDonald said he hasn't tried to test the arm yet but plans on practicing Wednesday. The injury isn't bothering him off the field.
"I'm able to use it in my day-to-day life, so I guess that's a good sign," he said.
McDonald was impressed with the way Tony Jerod-Eddie filled in for him, and added he wasn't jealous of Jerod-Eddie's interception.
"It was a blitzing call, and he did what he was supposed to do on that play, and he made the play," McDonald said. "We have a saying that we're always happy for another guy's success. I was happy for him. But I was also like, 'Man, if that would have been me, I could have got a pick, too.' But you have moments like that in games."
For second-round draft pick Carradine, who's returning from an anterior cruciate ligament injury suffered while with the Seminoles in a game against Florida last Nov. 23, the green light can't come fast enough to get on the field.
"I still have to wait until I get the say-so, but I feel great," he said. "I'm ready to get back out on the field at practice and start doing the things I usually do."
Carradine said he doesn't expect it'll take him long to get up to speed to play in a game.
When he started running six months after having ACL surgery, he wasn't sure how he'd get his speed back. But nearly a year following his surgery, he thinks he's as fast as ever.
"I feel like myself again," he said. "That's all we do every day is run and lift, so you don't have any choice to get stronger and better. I feel stronger and more in shape than I ever was before. I feel really good about coming back."
With all his rehab work, Carradine said his repaired right knee actually feels stronger than his left.
And even though he hasn't been practicing, he has been picking up the 49ers' defensive schemes in meetings and film sessions.
"I've watched a lot of film and spent a lot of time studying the playbook," he said. "As long as I have it mentally, and I know I have it because I've working on it, the physical part will be the easy part."
"I haven't been here for a Seattle preparation yet, but being here for the first day of Cardinal stuff, that intensity and focus is there," Skelton said.
Skelton, who added the Cardinals' preparation for the 49ers while he was there was so intense "everyone was walking on eggshells," said he isn't sure he can help the 49ers much in terms of Arizona's schemes. He did say he'll do everything in practice to try and simulate new Cardinals quarterback Carson Palmer.
"It's kind of hard, just because (the Cardinals) have had so much turnover the past year," he said. "New coaching staff, new offense, new defense, and a lot of new faces, too. It's almost unrecognizable. But they have a lot of talent. They've kind of put it together the last couple of games and done well."
Arizona (3-2) at 49ers (3-2), 1:25 p.m. Fox