49ERS Arm injury puts Rumph on the shelf for season

San Francisco remains winless and the defense is decimated by injuries.
SANTA CLARA, Calif. (AP) -- San Francisco cornerback Mike Rumph probably will miss the rest of the season, and at least two more defensive starters are expected to be out for the 49ers' game against Arizona this weekend.
Rumph will miss at least 8-to-12 weeks after breaking his right arm in the 49ers' loss to St. Louis on Sunday night. Defensive end Andre Carter won't play after surgery on his troublesome back, and linebacker Derek Smith is doubtful Sunday because of a leg injury.
NFL worst
The 49ers are winless after four preseason games and four regular-season contests -- and now the defense, which has allowed an NFL-worst 109 points, has been decimated by injuries. One-third of the 54 players on the 49ers' roster were featured on the injury report Monday.
Rumph, a third-year pro who started 13 games last season, was hurt in the second quarter. He will undergo surgery later this week to insert a metal rod in his arm.
Rumph missed the 49ers' two previous games with a groin injury.
"Through the season, I'm probably going to end up playing only three quarters," Rumph said. "Hopefully (the recovery time) can be quicker, but from what everybody's thinking about it, it's going to be a while."
Rookie Shawntae Spencer will start in Rumph's place Sunday against Arizona.
Smith, the 49ers' leading tackler in each of the last three seasons, underwent an MRI exam Monday to determine the extent of his leg injury. He was hurt early in the second quarter, and though initial X-rays were negative, he has torn ligaments near his ankle.
Bulging disc
Carter, who missed the 49ers' last three games, will be out at least three more weeks. Carter, a fourth-year pro, underwent surgery Monday to remove a cyst from his lower back. He also has a bulging disc in his back.
John Engelberger, the 49ers' other starting defensive end, also is questionable for Sunday with a strained abdominal muscle. Andrew Williams, expected to be a top backup, hasn't played this season because of a broken leg.
"Brandon Whiting is our healthiest defensive end," said coach Dennis Erickson, referring to the former Eagles lineman who has been beset by injuries to his back and shoulder since arriving in a trade for Terrell Owens.
But receiver Brandon Lloyd is expected to play after missing two games with a groin injury.