QB switches are generally bad news

The midseason quarterback change is rarely a good thing. Coaches don't voluntarily choose to switch starters midway through a season. It's a decision that usually is made for them. Either the starter gets hurt or he isn't playing well or he's Rex Grossman.

Think Mike Shanahan wanted to pivot to John Beck this week? Think again. That decision was forced on Shanahan by the fact that the quarterback he chose a couple of months ago proved that he actually isn't up for the job. Things go awry, and it's rarely a sign of a team racing toward the playoffs. It's typically a sign of the team that has gone off the rails, and it is usually very difficult to get the team back on track.

But it can work. Of the eight teams this season that have made an in-season quarterback switch -- including Denver, Minnesota and Washington, which will unveil new starters Sunday -- one has a shot at being as good, if not better, than it was before the switch: Oakland actually might be stronger when it eventually gets Carson Palmer under center rather than Jason Campbell, who was having a solid season before he broke his collarbone this past Sunday against Cleveland.

Palmer might not be ready to start Sunday, but he is a proven veteran. He has a history with Oakland coach Hue Jackson that dates to college. Jackson recruited Palmer to Southern California and was the Trojans' offensive coordinator for Palmer's first three seasons. Jackson was also the wide receivers coach in Cincinnati for three of Palmer's seasons there. He knows everything about Palmer -- the quirks, how his body moves, what he likes to do. Jackson has the knowledge that only experience with a player can bring.

And the Raiders already have other pieces in place. With Darren McFadden, they have a reliable rushing attack that is averaging 160 rushing yards per game, good for second in the NFL. Darrius Heyward-Bey has emerged as a legitimate threat, even though the wide receiving corps he leads is thin. Defensively, Oakland has one the nastiest, most physical front fours in the NFL, and, although there are uncertainties at the next two levels, the Raiders have a playoff-caliber defense. In a sign that Jackson's message is getting through to his players, the number of penalties is starting to decrease, as well.

Palmer isn't walking into Jacksonville. Oakland is 4-2 and has a legitimate shot to make the playoffs. Palmer's performance will be a huge key: How quickly can he knock off the rust from not having played or practiced since January? How fast will he pick up the Raiders' offense and terminology? Can he develop a rapport with his new teammates on the fly?

"My thought typically has been changing the quarterback is normally not real good," said Philadelphia offensive coordinator Marty Mornhinweg. "The one thing is a quarterback change can give you a little juice sometimes. But it's usually a small period of time. If the quarterback change comes and you're really a good football team, you've got a heck of a defense and the special teams are playing pretty well, it can work pretty well."

Mornhinweg has been through three midseason quarterback changes in his coaching career, two of which involved Jeff Garcia. The first with Garcia was in San Francisco in 1999, when Garcia, then a rookie, took over after Steve Young suffered what turned out to be a career-ending concussion in Week 3. In his first start the next week against Tennessee, Garcia completed 63.6 percent of his passes and threw two touchdowns in a 24-22 victory.

But over his next three starts, Garcia threw five interceptions and just one touchdown, and his completion percentage dropped severely. Garcia hit the rookie wall; he was so shaky that Mornhinweg had to bench him.

"It was more than a lull," Mornhinweg said. "It was ugly. We rushed for 220 yards and lost a game. It was ugly. We sat him down for a couple weeks and a bye, knowing that -- and this was the only thing -- he was so tough both mentally and physically that he could pop out of the thing, which he did.

"You go through some of those things when you make a quarterback change because you don't quite know."

Garcia started the last five games of that season and steadied himself. The next year, he threw for 4,278 yards and 31 touchdowns and made the Pro Bowl.

In 2006, Garcia and Mornhinweg were reunited in Philadelphia. The Eagles signed Garcia to back up Donovan McNabb, and, when McNabb tore his ACL against Tennessee in Week 11, veteran Garcia took over. Mornhinweg tweaked the offense to work to Garcia's strengths. Instead of relying on the big play, they put together methodical drives that relied on short and intermediate passes.

After losing to the Titans and then at Indianapolis, Garcia helped the Eagles win their last five regular-season games. Garcia was beloved in the locker room for being a fiery, tough player taking full advantage of a new opportunity. In the playoffs, the Eagles beat the New York Giants, then lost a dogfight at New Orleans.

Mornhinweg, who coached Palmer at the Senior Bowl in 2003, thinks the Raiders could have similar success this season.

"Philosophically, they are going to run the football and play good defense," Mornhinweg said. "[Palmer] doesn't have to come in right away and throw the ball 50 times. You get a win or two, and all of a sudden he gets the offense down. I think that has a chance to work really big, not that it will, but it has a chance. Obviously they think so, too, because they gave enough to get him. I think they thought they might be a great quarterback away from winning the whole thing."

Which makes the Oakland situation different from the others. Minnesota's Leslie Frazier is trying to get rookie Christian Ponder some experience. Denver's John Fox wants to get a look at Tim Tebow. And Shanahan apparently has decided that Grossman isn't the answer in Washington.

Oakland was forced into an involuntary quarterback change, but it might just work out in the Raiders' favor.

Ashley Fox covers the NFL for ESPN.com.