"I was surprised," Niners coach Jim Harbaugh said of the Broncos' onside kick in the preseason. "But I'm glad they did it. It's good for us because you always have to be aware of it."
Manning said he'd have gone out for another series had the Broncos recovered the onside kick. When they didn't, his day was done.
"I feel very comfortable where he is and rather than put him out there in harm's way, we took him out," Broncos coach John Fox said.
Caleb Hanie, locked in a backup battle with rookie Brock Osweiler to serve as Manning's primary understudy, underthrew Decker and former Broncos cornerback Perrish Cox intercepted at midfield. That led to Akers' first field goal, from 33 yards out. Hanie bounced back to throw a 5-yard TD pass to Dreessen that made it 24-10 at halftime.
"I don't want to say it's just the preseason because this is a time to get better," Niners linebacker Ahmad Brooks said. "It's a time you can really showcase what your team is capable of doing. I don't know but it's been a scary start to this point."
Smith finished 5 of 7 for 69 yards, and his pocket of protection was much better than it had been during the preseason.
"It was a little hard to get in a rhythm," Smith said, who was sacked just once. "I thought the young guys did a great job in the second half. We have some stuff to clean up obviously."
San Francisco's ground game, which had gained an NFL-best 378 yards through the first two weeks of the preseason, was stymied by the Broncos. With LaMichael James (left ankle) and Brandon Jacobs (left knee) sitting this one out, the 49ers were held to 14 yards on nine first-half carries, including two runs for minus-4 yards by Frank Gore.
That all changed after halftime as the Niners finished with 139 yards rushing. Anthony Dixon had a 26-yard TD run and Akers kicked field goals of 45, 21, 32 and 44 yards while the Broncos sputtered once again with Manning on the sideline.
Notes: Manning's passer rating of 148.6 was nearly 100 points higher than what it was (48.8) in the first two preseason games. ... Broncos rookie RB Ronnie Hillman made his preseason debut after dealing with a pulled right hamstring and gained 29 yards on 10 carries. "I'll plan on playing better next week and playing a lot faster," Hillman said. ... X-rays were negative on Ginn's right ankle. ... Rookie CB Omar Bolden bruised his left knee.
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