What has made Jackson so good for so long is his combination of strength and elegance. He has the build and tenacity of a true power back, but runs with the grace and agility of a game-breaker.
A play from Week 10 against the San Francisco 49ers' rugged defense encapsulates this fusion. The middle is usually a no-go area against a defensive front featuring Justin Smith and Patrick Willis.
Yet Jackson is still skilled enough to elude trouble at the line and still find the gaps. He does it with numerous smoothly-executed cuts.
The impressive thing about Jackson is his form. Notice how both shoulders are turned one way, seemingly indicating the initial direction he will run. However, Jackson's feet are always ready for his first cut.
In this example, his first cut takes him away from the nose tackle, in the direction of the yellow line. However, he will soon cut back to the middle.
Again notice how Jackson's feet are planted. They are loosely planted, enabling Jackson to shift his feet quickly and cut away from the direction his shoulders are turned.
His sudden moves drag the defense away and allow Jackson to beat pursuit to the other side.
Once he outmanoeuvres the initial penetration, Jackson's tremendous power can take over. He is fierce bruiser who demands gang tackling from a defense.
This play shows everything great about Jackson's game. The positioning of his body is ideal for ultimate manoeuvrability, while his footwork is nimble enough to support quick, sudden cuts.
That's how Jackson helps create many of his own gaps in a defense. His natural power then enables him to finish runs and consistently punish a defense.
Of course the mark of any elite running back is the ability to defeat eight-man fronts. Jackson is still able to use the agility and range he showed on this play, to undermine overloaded run fronts.
A perfect example is a play from Week 17 against another tough run defense, the Seattle Seahawks. The Seahawks are supplementing their powerful front four with an extra man on both sides.
On one side, linebacker K.J. Wright has joined the line. On the other, safety Earl Thomas is creeping up, preparing to execute a run blitz.
Jackson will again use his footwork and fluid movement. He will quickly make the eighth man a non-factor.
Again Jackson's shoulders are squared one way, in the direction of the yellow arrow. Yet it is the agile footwork that helps Jackson get free.
His plant foot is slightly lifted, while the other is completely raised from the ground. This is the perfect starting point for one of Jackson's favourite and most distinctive moves, the jump cut.
It will allow him to turn into the hole at the angle of the blue arrow. Once there Jackson can jump through the initial wave of defenders.
Now through the hole, Jackson's again relies on brute force to batter his way for extra yards. Even a thumping middle linebacker like Bobby Wagner is likely to bounce off Jackson in full force.
These two runs came against the fourth and 10th ranked run defenses of 2012 respectively. That shows Jackson can still gain the tough yards against consistently stout defenses.
He still possesses the balance, agility and strength to consistently gain positive yards. Yet any player deemed worthy of the "elite" tag has to also show a knack for the big play.
One run from Week 12 against the Arizona Cardinals shows Jackson is still able to to stretch the field. At the handoff, Jackson displays his familiar blend of flawless coordination and quick thinking.
His shoulders are again square to the initial direction of the run. While the path of his first quick cut is also clear.
Jackson's agility and footwork again take him past the first wave of penetration.
The positioning of his feet shows the inside foot again loosely planted, with the second foot already coming up from the ground. This enables Jackson to execute his sharp about-turn in one sudden and seamless move.
Now he has turned back across and is running against the grain of the Cardinals' slanting defense.
Jackson is now able to pivot to the outside and use his speed around the corner.
Jackson beat the pursuit down the sideline and completed a 46-yard run. The veteran amply demonstrated that he is still quick enough to outpace a defense on the edge.
These runs reveal what makes Jackson an elite offensive talent. He poses a unique dilemma to every defense he faces.
Normally when facing a punishing power-back, a defense doesn't want to play passively. They want to attack aggressively, before a 240-pound battering ram like Jackson builds up a head of steam.
However, Jackson is quick and shifty enough to exploit those attacking tendencies for major gains. In fact, a defense is better served simply standing back and waiting for Jackson to make his first cut and come to them.
However, if a defense opts for that approach, it had better bring numbers to take Jackson down, or he will overpower the initial tackler.
As dominant as he can be as a runner, Jackson has also remained a credible receiving threat. He has tallied over 300 yards in receptions in each of the last five years.
An example from Week 6 against the Miami Dolphins shows how effective Jackson is as a pass-catcher.
The Rams are facing 3rd-and-13, deep in their own territory. The Dolphins are setting up a blitz and Jackson's first responsibility will be to block rushing linebacker Kevin Burnett (56).
Jackson slams into the block and knocks Burnett out of his blitz path.
He then quickly releases into the open field. Jackson immediately presents quarterback Sam Bradford with an option and escape from the pressure.
Once he gets the ball in his hands, Jackson's typically nimble moves create a significant gain. He uses that trademark jump cut to leave a linebacker grasping the ground, before powering into the safety.
Jackson would gain 22 yards on the play, getting the Rams out of serious trouble. That a team is even willing to go to Jackson on 3rd-and-13, proves his continuing excellence in the open field.
Whether as a runner or as a receiver, Jackson sill boasts the skills to terrorise NFL defenses. It's a case of pick your poison when facing the dynamic veteran.
Either try to stand up and match his awesome power, or attempt to keep up with his elusiveness. Yet it is Jackson's amazing coordination that really keeps him elite.
On any given run, the positioning of his upper and lower body is flawless. That's a gift and habit that doesn't leave a player, despite the 29-year-old approaching the age where many at his position decline.
Expect no such sudden slump from Jackson. For all the claims that he is washed up, Jackson still recorded his eighth straight 1,000-yard season in 2012.
He's one of only six runners in league history who can boast that distinction. His average per carry remains healthy and above the 4.0 mark, where it has been in four out of the last five seasons.
So Jackson's claims that he can still be a "bell-cow" running back, are perfectly justified. He is easily the best running back available in free agency.
The team lucky enough to land Jackson will certainly be adding an elite talent to their offense.
All screenshots courtesy of Fox Sports and NFL.com Gamepass.