AP Sports Writer
SAN FRANCISCO (AP) -- First, tight end Vernon Davis went down with a concussion. Then it was standout rookie safety Eric Reid.
Perhaps more concerning for San Francsico than a lackluster 10-9 defeat to the Carolina Panthers on Sunday is the loss of a key player from each side of the ball along with a handful of other injuries as the reigning NFC champions head into the season's stretch run.
With two tough road games up next, too.
Drayton Florence intercepted a pass by Colin Kaepernick in the final minute to seal it as the Panthers snapped the 49ers' five-game winning streak.
Coach Jim Harbaugh didn't yet know much about how Davis and Reid were doing.
"Just saw them in the locker room and they seemed as good as could be expected," he said.
Still, both players will be put through a concussion protocol involving several different steps and an evaluation once they become symptom-free.
The Niners (6-3) hit the road next week for New Orleans, then go to Washington.
"We'll do what we do, bounce back, regroup, refit and reorganize and come back this week," Harbaugh said.
Davis didn't return after sustaining a concussion in the second quarter, then Reid went down on a helmet-to-helmet hit on Mike Tolbert in the third. Earlier, Reid recovered a fumble to give him five takeaways in an already-stellar rookie season that also includes three interceptions.
Graham Gano kicked a 53-yard field goal with 10:05 remaining that held up as the Panthers (6-3) twice shut down Kaepernick on last-ditch drives with swarming defense.
DeAngelo Williams broke two tackles for a 27-yard touchdown run late in the first half that pulled Carolina within 9-7. Gano missed wide left on a 48-yard field goal in the third period, but came through later.
San Francisco got the ball back with 5:25 left at its 1, then again with 1:02 to go.
Phil Dawson kicked a season-best 52-yard field goal among his three for the 49ers, who failed to recover a pair of Carolina fumbles in the closing moments. Jonathan Stewart fumbled and Mike Tolbert pounced on the ball. Cam Newton recovered his own bobble.
This was hardly the highly touted showdown between 2011 No. 1 overall pick Newton and Kaepernick, the sixth quarterback drafted that year, in the second round. They roomed together during the scouting combine.
Kaepernick went 11 for 22 for 91 yards with an interception and was sacked six times for a 42.0 passer rating. Newton was only slightly better, going 16 of 32 for 169 yards, an interception and four sacks for a 52.7 rating.
"It's unacceptable. We have a number of weapons on offense. We just have to do a better job of making it happen," wide receiver Anquan Boldin said. "Offensively, we didn't get it done. It's all on us."
For two teams that have been putting up points at a prolific pace for the past month, the defenses dictated this one. Frank Gore had 16 carries for 82 yards, accounting for most of San Francisco's 151 total yards.
Dawson put San Francisco ahead on a 52-yard field goal on the team's opening drive, then kicked second-quarter field goals of 43 and 25 yards.
But Kaepernick could never get his team in the end zone.
"For the most part, I don't really think they did anything that necessarily confused us," 49ers center Jonathan Goodwin said. "They only gave up nine points. It's hard not to give them credit. We expected it to be a physical game. Did we expect to only score nine points? Nah."
49ers pass-rushing specialist and 2012 All-Pro linebacker Aldon Smith played about a dozen snaps after missing five games to undergo treatment for substance abuse.
"Oh, it's special to see a dominant player like that back," cornerback Tarell Brown said.
Wide receiver Mario Manningham started and had three catches in his season debut, nearly 11 months after a serious left knee injury that required surgery.
When San Francisco's Andy Lee had his punt blocked at the end of the first quarter, Florence tried to get out of the way, but went to grab the ball at the last second and it got away from him. Reid wrestled the ball from Josh Thomas for his second fumble recovery of the season and fifth takeaway.
Carolina got going after managing only minus-7 yards passing and 12 total yards in the first quarter. The Panthers finished with 250 total yards.
"This one really did come down to the way the defense played," Panthers coach Ron Rivera said. "Any time you put yourself in a position where you can force the other team to kick field goals, you get a chance to win."
Notes: The 49ers also lost TE Garrett Celek to a hamstring injury in the first quarter, while DT Ray McDonald hurt an ankle. ... Panthers LB Chase Blackburn did not return in the second half because of a foot injury.
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