The San Francisco 49ers could hardly have looked more overmatched in the first quarter of their rematch with the Philadelphia Eagles.

Thankfully the game is longer than one quarter.

San Francisco survived several big punches from the Eagles in the 49ers' first meeting with Philadelphia since the NFC Championship Game and went into the half leading 14-6. Here are our first-half observations.

49ers cling on in first quarter

San Francisco was in danger of getting blown off the field in the opening quarter.

While Philadelphia's opening two drives saw them surge into the red zone behind a series of explosive plays, the 49ers' offense was stuck in reverse.

Indeed, in the first quarter, the 49ers' net yardage tally was minus six compared to 124 for Philadelphia.

How did they survive? Red zone defense. The 49ers came up with stops on both occasions, Charvarius Ward registering a league-leading 16th pass breakup on third down against A.J. Brown on the first drive and Javon Kinlaw killing the second with a fortunate sack after Jalen Hurts slipped on the turf.

Those stops held the Eagles to field goals proved crucial as the 49er offense found its rhythm in the second quarter.

Aiyuk and Kittle get things going

The San Francisco attack looked in deep trouble on its third drive after a false start put them on their own 10-yard line on second and 15.

But a pair of completions to two of the 49ers' dependable playmakers got San Francisco its opening first down of the contest, with Brandon Aiyuk and George Kittle coming to the fore ahead of Deebo Samuel and Christian McCaffrey.

Aiyuk finished the drive with 23 yards and and a touchdown reception on third and goal from the two-yard line, with San Francisco getting to the point on the field in large part thanks to a 32-yard catch and run by Kittle.

McCaffrey and Samuel joined the party as the 49ers scored again on an impressive fourth drive through their do-it-all running back, but it was the wide receiver who cedes the limelight to his more celebrated teammates who got the train on the tracks.

San Francisco secondary puts on the clamps

The 49ers were able to build an eight-point lead because the defense improved significantly after the opening two drives, their next two each ending in a punt.

Frustration for Hurts was a theme in the second quarter, the MVP frontrunner consistently running out of time after holding the ball because of blanket coverage in the secondary from the Niners.

The second quarter was another vindication of the 49ers' post-bye decision to bench starting slot corner Isaiah Oliver and bring Ambry Thomas into the lineup on nickel downs alongside Ward and Deommodore Lenoir.

Philadelphia, though, has won four straight games while trailing at the half. The 49ers won't be celebrating anything they've done to this point. The job is far from finished.

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