SAN FRANCISCO --Screens. Quick slants. A quarterback running around, breaking the pocket and gaining yards with his legs. San Francisco's offensive game plan on Sunday was to negate the blitzing Eagles defense by getting the football out of the hands of quarterback J.T. O'Sullivan, and while the performance wasn't all that pretty, it was good enough to put the Eagles on their heels for most of three quarters at Candlestick Park.

"We never got down on ourselves," said safety Quintin Mikell, who contributed one of many big plays in the fourth quarter as the Eagles completed a stunning defensive turnaround to beat the 49ers, 40-26, winning the battle in the fourth quarter, 23-0. "You keep battling and things are going to work out in your favor."

Continuing a struggle that started in Chicago, the Eagles defense couldn't get off the field against the 49ers on Sunday -- until it mattered most. San Francisco countered Jim Johnson's pressure by punching back with an impressive array of three-step drops by O'Sullivan, a spattering of runs by Frank Gore and enough protection to keep O'Sullivan upright. San Francisco entered the game last in the league in sacks per pass play; the Eagles had exactly zero sacks until the fourth quarter. Philadelphia registered zero three-and-outs against the 49ers offense until the fourth quarter.

A defense that opened the season blitzing the Rams into submission, by crushing the Steelers with a sackfest and then turned in a great third quarter against the Bears turned it on in the fourth quarter.

DE Parkerreturns INT for TD

Late in the game, the defense had a chance to make a stand. With 11:31 to go and the 49ers up 26-24, the defense needed a stop. On first and 10, Trent Cole pressured O'Sullivan into an incomplete pass. Then Sheldon Brown had excellent coverage on another throw. On third and 10, Omar Gaither smothered Gore on a screen pass and the 49ers were forced to punt. The Eagles put together a drive that resulted in points that gave them a 27-26 lead.

Then, with 7:38 remaining, the 49ers had the ball on their 38-yard line. It was time for another defensive stand. Gaither stopped Gore on a run. Juqua Parker stayed home on a handoff to tight end Delanie Walker and tackled him for a 10-yard loss. On third down, O'Sullivan rolled right and threw in the middle for Bruce, but Quintin Mikell was there with the interception. Mikell returned the pick 41 yards to the 49ers' 7-yard line.

"I had a good jump and a good read and the ball was there. I was in the middle of the field and it came right to me," said Mikell.

But the offense scored just three points, and instead of putting the game away, made the defense stand up again.

With 5:08 to go, the 49ers had the ball on their 19-yard line. Gore was stuffed on a run to the left side, gaining just one yard. After a 5-yard penalty on the 49ers, O'Sullivan scrambled for 11 yards, setting up a third-and-3 play. Trent Cole stepped up there, sacking O'Sullivan and forcing a fumble that Chris Clemons recovered. The Eagles scored three more points to lead, 33-26.

Finally, Parker picked off an O'Sullivan pass and returned it 55 yards, and the celebration was on. The game was over. The defense, maybe, was all the way back.

"You hope so," said Gaither, who had seven tackles. "They hurt us with some quick throws and big plays and we made a couple of adjustments and rode that. We know what we can do. We have to go out and do it for 60 minutes. That is the key. That is what we are striving for." Eagles-49ers: Parker Interception