"You know what? It doesn't matter to us," coach Mike Singletary said this week. "I think there are pros and cons to both quarterbacks, so I'm excited for the opportunity we have to play the Eagles."
It will probably matter when the 49ers defense doesn't have to chase Kolb around the field as it would have had Vick been named the starter. But a rib injury will keep Vick, who has 187 rushing yards and a 7.2-yard average, out of the game. Sweet favor.
Kolb is merely regaining the position he lost to Vick after suffering a concussion in the season opener. Vick played so well in his place (a 108.8 passer rating, six TDs passing and one rushing) that coach Andy Reid, after declaring that Kolb was still his starter, reversed field and gave the job to Vick full time.
Now Kolb is back, and although he's far less versatile as a runner, the 49ers believe they still must pay attention.
"It's always hard to cover Vick because he can scramble and get out and make a no play into a 50-yard play," defensive coordinator Greg Manusky said. "This kid does the same thing. Kolb, he's got some ability to scramble and feels inside how he can get out, and he's done that in the past. So we have got to protect that as well."
It's a big game for both teams. The 49ers are 0-4 but almost beat the defending Super Bowl-champion New Orleans Saints in their only home game this season. A win would temporarily wipe away all the dysfunction they've suffered since training camp. The Eagles are 2-2 but are coming off a disheartening 17-12 loss at home to the Washington Redskins and former Eagles favorite Donovan McNabb.
Although Vick won't be there, the Eagles will still have their two deep threats, wide receivers DeSean Jackson and Jeremy Maclin, whose speed will test the 49ers secondary. Rookie safety Taylor Mays will have to provide help to the team's cornerbacks to keep Philadelphia from eating up big chunks of yards.
"I think both those receivers really can get down field," Singletary said, "and I think the most important thing for us is to have our guys try to get our hands on them early and slow them down before they get up field, and that's going to be real key."
The Eagles won't have cornerback Asante Samuel, who's been ruled out because of a concussion, but running back LeSean McCoy (273 yards on 50 attempts) will be available despite a broken rib. He'll be wearing a flak jacket.
Offensively, the 49ers will probably look to stretch the field. Singletary said as much this week, and with speedy Ted Ginn Jr. expected back from a knee injury, now would be a good time. Quarterback Alex Smith has been checking down much too often this season, in part because of protection problems, and that's why running back Frank Gore (29 catches) is the team leader in receptions.
Singletary said Friday he would also look to blend running back Brian Westbrook, a former Eagle into the offense.
"We certainly tried to work toward that this week," Singletary said. "We'll figure it out. It depends on the game – the tempo, the style. We're going to try and get him out there. How much, I don't know."
Westbrook said, "Obviously, I haven't had an opportunity. Hopefully, this week will be the week when I get some chances where I can make some people open their eyes and say, ‘We should've gotten this guy on the doggone field a little earlier.'"
INJURIES: Tight end Delanie Walker (high ankle sprain) has been ruled out. Punt returner Kyle Williams (finger) is questionable. Guard Chilo Rachal (knee) is probable. Singletary would not say if Rachal will start ahead of Adam Snyder.