What it means: The 49ers improved to 9-3-1, maintaining their lead in the NFC West on a day when Seattle (on its way to 8-5) was winning big and St. Louis (6-6-1) also won. That was critical for San Francisco as the team heads into more difficult road games against New England and the Seahawks.
What I liked: Colin Kaepernick completed 18 of 23 passes for 185 yards, good for a 100.2 NFL passer rating. His 50-yard scoring run in the final minutes put away the game for San Francisco.
Second-year outside linebacker Aldon Smith, who entered the game tied with Fred Dean for the single-season 49ers sack record (17.5), moved into sole possession of the mark with a first-half sack.
Rookie running back LaMichael James picked up 10 yards on his first carry of the season. He looked good. Receiver Michael Crabtree continued to produce after the catch. Frank Gore topped 1,000 yards rushing for the season and had a touchdown run.
The 49ers held the Dolphins to 227 yards.
What I didn't like: Kaepernick took four sacks, and the offense wasn't all that cohesive. San Francisco allowed a touchdown drive early in the fourth quarter after taking a 20-6 lead. The Dolphins were more efficient than the 49ers on third and fourth downs. That was clear again when San Francisco went three-and-out after Miami pulled within 20-13. The 49ers had converted only one of eight (12 percent) third-down chances to that point, compared to five of 11 (45 percent) chances for the Dolphins.
San Francisco allowed three sacks to Miami's Cameron Wake.
A 15-yard penalty against the 49ers for NaVorro Bowman's hit on Ryan Tannehill gave Miami a first down at the San Francisco 35-yard line in the final five minutes. Bowman made an aggressive play. He did not appear to do anything dirty. But officials have been instructed to err on the side of protecting quarterbacks. They did that on this play. Penalties have been a problem for the 49ers recently. That was the case late.
What's next: The 49ers visit the New England Patriots in Week 15.