In Ryan's case, he might be a victim of his own success. The Raiders finished with the third-ranked defense last season in terms of yards allowed per game and returned all 11 starters.
This season, the Raiders enter Sunday's regular-season finale against the San Diego Chargers ranked 26th in the same category. In other words, first-year coach Lane Kiffin doesn't have to look far for a scapegoat.
"It has been disappointing to return 11 starters," Kiffin said. "We definitely felt that the defense was going to be the strength of our team this season, coming off of last season and hoping that we'd improve into this season."
Just the same, he added, the lack of sustained success offensively and on special teams have played a hand in the defense's poor showing.
Sure enough, the offense is 26th in terms of yards gained per game and every bit as much to blame for Oakland's 4-11 record, as are special teams that have allowed their share of back-breaking plays.
However, Kiffin is in charge of the offense, and coaches aren't known for firing themselves.
Ryan said Wednesday that he isn't worried about his job security, even if he hasn't received any assurance from Kiffin about the final year of his contract.
"I'd be out of a job for two minutes," Ryan said. "Who are we kidding? I'm not worried about it.
To a man, Ryan's players say it would be a mistake to fire the defensive coordinator. Ryan can't be faulted for the myriad missed tackles, blown assignments and flat-out underachieving by certain players, they say.
Cornerback Nnamdi Asomugha said he and his defensive teammates are comfortable in Ryan's system. Making a change for the sake of change would serve only to retard the unit's progress.
"We were third in the league in defense, so you come back with the same guys and you think you're going to be better," Asomugha said. "That's just how it goes sometimes. You just never know what you can expect, so it's definitely disappointing.
"The expectation level that we had coming into this year was so high, we didn't know if we'd be able to reach it, but we knew we had a chance. We just did a complete 180."
Given that, there's no reason to think the Raiders can't do another 180-degree turn next season, Asomugha said. Ryan said he was part of just such a turnaround when he was with the New England Patriots.
Kiffin said Wednesday that he has pondered changes for next season but that none has been made just yet.
"I want to make sure that I feel extremely comfortable in the direction that we're going, what we're doing, we're making sure that we're putting our players in the best position to win, and that we're improving," Kiffin said.
Oakland's precipitous drop in production defensively has caught everyone off guard in Raiders land. Most of the concern entering this season centered on an offense that scored only 12 touchdowns last season.
Yet, from the outset, the defense has struggled. There have been flashes from play to play, game to game, but not the kind of sustained success Ryan and others became accustomed to last season.
"We've given up a lot of big plays, whatever the case may be, whether it be tackling or whatever," Ryan said. "It's unfortunate and a little bit stunning to me, but that's the way it is."
The players have heard the rumblings that Sunday might be Ryan's final game with the Raiders. That doesn't mean they have to believe the speculation.
"It's tough," second-year safety Michael Huff said. "Rob-O's our guy. Rob-O brought me here, I love playing for him, and so anytime you hear all this stuff, you don't know who's going to be here next year and all that, you kind of feel bad for him because he's a great defensive coordinator and a great guy."
Contact Steve Corkran at email@example.com