ALAMEDA, Calif. (AP) As if the Oakland Raiders' defensive problems weren't bad enough, another injury will force them to use a third-stringer at strong safety.
Usama Young left Sunday's 24-13 loss to Arizona with a significant injury to his left knee. He underwent an MRI on Monday and ESPN reported that he has a torn ACL and MCL in the knee and will miss the rest of the season.
With starter Tyvon Branch already out for the season with a broken foot, the Raiders (0-6) once again are forced to turn back to Brandian Ross, who struggled in that role last year after Branch got hurt.
Ross was released after training camp this summer and signed with Miami before returning to Oakland late last month. After spending time preparing at cornerback and safety in 2013, he feels more prepared to step in as a strong safety this season.
''Last year I played a lot of different positions and I was asked to do some things that I wasn't accustomed to doing,'' Ross said Monday. ''My body wasn't ready for it mentally. It was tough. This year I'm doing less and it's very simple for me.''
The Raiders are already dealing with a season-ending concussion for middle linebacker Nick Roach and now have more issues in the middle of their defense.
Ross will be counted on to help the Raiders reverse their struggles on third-down defense. Oakland has allowed opponents to convert 52.9 percent of third-down tries, a mark that would be the highest ever recorded for an entire season.
The problems were particularly costly against the Cardinals, who converted 9 of 15 third-down tries on Sunday. Those plays included Arizona's first two touchdowns and a pair of third-and-8 conversions on a clock-draining drive that led to a late field goal that put the game out of reach.
''We're for the most part able to play good football on the early downs but for whatever reason, man, third downs, I don't know if there's a lack of focus or what it is on third downs but it is definitely our Achilles' heel right now,'' safety Charles Woodson said.
For the season, opposing quarterbacks have completed 44 of 56 passes on third downs for 499 yards, eight touchdowns, no interceptions and a 143.4 passer rating.
Interim coach Tony Sparano plans to deal with these woes by placing more emphasis on third downs in practice Wednesday, so the players have more time to digest the fixes. The Raiders typically work on base situations Wednesday, third downs on Thursday and red zone on Friday.
''One of the things that I need to do is stop and look and say, `OK, this is a problem we've identified. How do we get more at-bats here? How do we get more information to the players? More corrections to the players earlier in the week so they have more time to digest that,''' Sparano said. ''Because that's really where the moving parts are.''
Woodson has been one of the few bright spots on the defense this season, intercepting his second pass of the season Sunday and making big stops all over the field.
Now the rest of the defense needs to play as well as the 38-year-old Woodson.
''He's flying over piles, diving into piles and he's not taking anything for granted,'' Ross said. ''He's chopping guys at the knees. He's like almost 100 and he's doing it. If he can do it at this age why can't I.''
NOTES: Sparano had no update on the status of DE Justin Tuck (left knee) and FB Marcel Reece (quad), who missed Sunday's game with injuries. ... Sparano also said DE LaMarr Woodley was limited in the game by an undisclosed injury.
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