After passing former 49er great, Joe Perry, during the 2011 season, Frank Gore became San Francisco's NFL-franchise leader in rushing with 7,625 yards.

From 2005, when Gore entered the league, through 2011, Gore is ranked fourth in rushing yards and attempts per game.  Amongst active players, Gore is in the top five for most touches during his career, and the players above him are all older.

The 49ers' record during Gore's tenure, up until the beginning of last season, was 37 - 59, having never finished with a record above .500, and having never made the playoffs.

Indeed, Gore has been the stereotypical workhorse back, and San Francisco's inept offense and inept coaching staff has grinded him into the dirt for the better part of a decade.  Finally, last year, they got it right, going 13 - 3 and winning a playoff game - the first of Gore's prestigious career.

But while the 49ers are finally stepping things up, Gore has been losing a couple steps of his own.  He still has a certain measure of quickness, and even late into last year was exploiting gaps for large gains; but he was getting caught from behind and tackled where in the past he would have easily made the endzone.

They accounted for some of that last year, giving 2011 4th round pick, Kendall Hunter, plenty of playing time in place of Gore while he was injured during parts of the season, or to give Gore a rest; and similarly utilizing Hunter as a change-of-pace back.

Hunter, however, still only touched the ball 96 times in what was a clear back-up role to Gore.  Expect that to change this year.

Not only has Hunter proven himself in limited touches as a capable back, but he even had a couple big plays in the passing game last year - something San Francisco has been sorely missing through the years; and as Gore's 28-year-old, workhorse clock slowly ticks away, Hunter will be picking up the slack.  But he won't be the only one:

This offseason the 49ers acquired All-American running back out of Oregon, LaMichael James, with their 2nd round pick.  James set career and single-game rushing records while at Oregon and was a 2010 Heisman Trophy finalist, having almost-led the Ducks to a National Championship that year.

San Francisco also went out and signed former-Giant, Brandon Jacobs, to a one-year deal after him and New York could not come to an agreement.

Entering training camp, all four of these men - Gore, Hunter, James, and Jacobs - are primed for a roster spot and will be utilized during the regular season in what is poised to be one of the most dangerous running games in the league.

Hunter will continue to garner touches as the change-of-pace back, showing most of his skill outside the tackles.  James will likely be trained for Gore's position as the feature-back and will also be utilized, along with Hunter, as a legitimate threat in the passing game - someone who can take a dump off and go 30 yards.  Jacobs will primarily be brought in for the power running game to muscle out short-yardage - something the 49ers struggled greatly with last year.

Gore will continue his role as the more-or-less feature back, but he will be expected to earn his touches this year.  Any slight injury, or off-game, and Gore will see his touches limited in favor of the younger duo of Hunter and James.

What is most interesting, however, is that the 49ers are building a veritable running back by committee attack, and all four men will get their fair share of touches in different situations.  49er head coach, Jim Harbaugh, loves diversity in all aspects of the offensive game, and by bringing in players of different skill sets, we can expect even more exotic formations than last year.

More importantly, with both Hunter and James in the backfield - at the same time, even - the 49ers have added some much-needed speed and explosive capability.  Add that to the additions of Randy Moss, Mario Manningham, and AJ Jenkins on the outside, and San Francisco might just have one of the most dangerous offensive units in the entire NFL.