As it has been for several years, the San Francisco offense revolves around the hard-charging running of veteran Frank Gore, who will be looking to break the 1,000-yard barrier for the sixth time in his distinguished eight-year career sometime early in the first half of Sunday's game. Gore is fifth in the NFC with 972 yards rushing, and though the 49ers added several new parts this year to make their offense more explosive, the attack is still built around Gore, a three-time Pro Bowler. Gore has the power to run between the tackles but his style is more of a slasher whose burst breaks him quickly into the second level. Gore is the feature back of the NFL's second-ranked rushing attack, which works behind a big and bruising line that sets the tone with the physical play of left guard Mike Iupati and right tackle Anthony Davis. Iupati, who is having a Pro Bowl season, will pull often to lead Gore through holes, and the 49ers like to run several trap and isolation plays that hit quickly off the snap. Center Jonathan Goodwin, Pro Bowl left tackle Joe Staley and right guard Alex Boone round out an offensive line that works well together, especially blocking for the run. Boone, the team's third tackle last season, has made a smooth transition to right guard as the unit's lone new starter this season. The Niners, however, are in the process of looking for a new backup to Gore after speedy Kendall Hunter was lost for the season two weeks ago at New Orleans with a torn Achilles. Hunter has been a tremendous change-of-pace complement to Gore the past two seasons and had rushed for 371 yards before his injury. Hunter was missed during last week's overtime upset loss to the Rams, when Gore was forced to carry the ball a season-high 23 times but was limited to just 58 yards rushing. Big Brandon Jacobs was the only other back to carry the ball for San Francisco and managed just six yards on four carries. The 49ers may look to second-round draft pick LaMichael James, who has yet to play in a game this season, to add some spark and outside speed to the attack similar to the way Hunter did before he was hurt.
DOLPHINS RUSH DEFENSE
The strength of the Dolphins defense for the past several years has been stopping the run, and that hasn't changed. Miami ranks eighth in rushing defense in the league in terms of yards allowed per game, but the Dolphins are fourth in terms of yards per rushing attempt. The Dolphins have allowed eight of their 12 opponents to under 4 yards per carry, including holding New England to 3.4 yards last Sunday. The key player in the run defense is 2011 Pro Bowl selection Paul Soliai, a 330-pound former nose tackle who's a load in the middle of the defensive line. The other starting defensive tackle Randy Starks possesses more pass-rushing ability than Soliai but he's also very good against the run. Defensive end Cameron Wake is known for his pass-rushing ability, but his coaches — in particular defensive coordinator Kevin Coyle — have raved about his work against the run all season. Of the starting linebackers in Miami's 4-3 defense, middle linebacker Karlos Dansby probably is the most active when it comes to stopping the run. The one starter in the secondary who's made an impact in run support is safety Reshad Jones, who is putting together a Pro Bowl-caliber season.
49ERS PASS OFFENSE
The 49ers still are in transition with their offense in general and passing game in particular now that the reins have been handed to second-year quarterback Colin Kaepernick. The 49ers were doing just fine with Alex Smith behind center before Smith suffered a concussion on Nov. 11 against St. Louis – Smith is the NFL's third-ranked quarterback with a passer rating of 104.1 and leads the league with a 70.0 completion percentage. Despite those numbers, Smith has yet to play another snap since his concussion as Kaepernick took his opportunity and ran with it – both literally and figuratively. Kaepernick has special athleticism and a big arm, and he gives the 49ers more big-play capability than Smith and provides the offense a different dimension with his ability to throw deep. Kaepernick also is a threat to scramble from the pocket for big yardage – he led the 49ers with 84 yards rushing last week, including a 50-yard run, the longest for any 49er this season. Kaepernick is averaging 8.4 yards per passing attempt while completing 65.1 percent of his throws for a QB rating of 96.7, and that has convinced coach Jim Harbaugh to stay with the youngster for the playoff stretch run. Kaepernick has capable receivers on the edges with Michael Crabtree, who is developing into a solid No. 1 wideout, and veterans Randy Moss and Mario Manningham, though Manningham has a shoulder injury suffered last week and is doubtful to play against the Dolphins. Crabtree leads the 49ers with 57 receptions for 668 yards and has been a go-to guy on third downs. Moss has been used in a limited fashion during his first season with San Francisco but averages 15.6 yards a catch and still has the big-play ability that's made him one of the league's all-time great receivers. The Niners have another big-play weapon in versatile tight end Vernon Davis, who has been underutilized in the attack this season. Davis is averaging 13.6 yards and has five touchdowns among his 37 receptions this years, but has just two catches in the past two games. San Francisco quarterbacks have been sacked 34 times this season, so there is an opportunity for the Dolphins to disrupt the San Francisco offense and make plays pressuring the Niners on passing downs.
DOLPHINS PASS DEFENSE
The Dolphins rank only 27th in the league in pass defense, but they're coming off an impressive effort against Tom Brady and the New England Patriots when they held the future Hall of Fame quarterback to his worst passer rating in more than two years. Miami has juggled his secondary throughout the year, starting with the trade of 2009 first-round pick and former starter Vontae Davis — the younger brother of Vernon Davis — to Indianapolis. Richard Marshall was signed from Carolina in the offseason as a free agent, but he was placed on IR with a back injury and was replaced in the starting lineup by 2010 fifth-round pick Nolan Carroll. The best player in the secondary this season has been safety Reshad Jones, who had a sack against New England and an interception he returned for a touchdown, only to see his score nullified by a penalty on the return. His interception was the first against Brady in six games. Miami's linebackers are pretty adept in coverage, most notably veteran Kevin Burnett. Defensive end Cameron Wake, who joined the Dolphins in 2009 after starring in the Canadian Football League, leads Miami with 11 sacks. Defensive tackle Randy Starks is second on the team with 4.5 sacks, but the Dolphins would like for someone to emerge as a consistent pass-rushing threat to complement Wake. Rookie third-round Olivier Vernon has shown flashes of pass-rushing potential.