With the move, the Spurs announced their intention to compete punch-for-punch with the mega-talented defending champions.
Tim Duncan wanted to carry that status at least once more, and the front office and ownership group needed to spend big to give him that chance.
The result of trade talks that began near the February trade deadline, Jefferson's arrival instantly infused the roster with the kind of athletic performer that had torched San Antonio's title hopes in 2006, 2008 and 2009.
The best leaper on the squad since David Robinson, the former Finalist also brought defensive chops—and most have forgotten how good a defender Jefferson was in his first years with New Jersey—and a thirst for a title.
Adding a fourth 20-point scorer to a proven winner, the team's brass thought, would give them a healthier shot at matching the Lakers high-powered offense.
However, coach Gregg Popovich and GM R.C. Buford had more than purple and gold in mind when they pursued the former Arizona Wildcat.
Jefferson will matter tonight, too, when the Spurs bump, grind and claw with their pesky I-35 rivals.
The squad's previous two playoff battles with North Texas' blue and green franchise ended in painful, emphatic fashion.
The Mavericks won game seven at the AT&T Center in overtime in 2006 to eliminate the Spurs from a title defense.
Dallas' five-game thrashing played a large role in the front office's decision to spend more money this offseason than ever.
The Mavericks' not-so-secret, deadly ingredient: Josh Howard, the dexterous Wake Forest forward the Spurs discarded in the 2003 draft to save money for a full-on Jason Kidd pursuit in free agency.
Tim Duncan has usually cancelled out Dirk Nowitzki's production with his interior play.
Tony Parker has rarely lost a point-guard battle with anyone on the Mavs, not even Devin Harris. Even if the two played to a draw and if Harris frustrated Parker like few could then, the duels were close.
Manu Ginobili more than made up for Jerry Stackhouse and Jason Terry's hot-as-lava production in 2006.
Howard? He has killed the Spurs and mutilated their remains in many meetings.
Enter Jefferson, the player Popovich will count on to stop the bleeding in this always-fiery duel.
The Mavericks do things against the Spurs they have not done consistently against anyone else.
They manage to conjure a rare anger anytime they see silver and black on the schedule.
Games against San Antonio seem to mean even more to Dallas than rumbles with the Lakers or Boston Celtics.
With Duncan's window as a superstar, franchise-level talent predicted to close in three years, maybe sooner, these Texas two-steps are equally important for the Spurs.
Contrary to opinions based on box scores and two paltry shooting performances, Jefferson has fit seamlessly in his third NBA home.
The Spurs' played some of the worst defense in franchise history in the last week, but Jefferson was not the guilty party.
Though Popovich praised his players' effort after a hard-fought 131-124 victory over the Toronto Raptors Monday night, giving up that many points in regulation displeased him, to say the least.
The pitiful-defense transgressors have included everyone except Jefferson and Duncan.
No one should have expected a roster with so many new parts to click in the first month of the season. If you did, welcome to reality.
Jefferson will haul a heavier load tonight if Tony Parker and Tim Duncan sit out with ankle ailments. The San Antonio Express-News reported both as "doubtful" for the tilt with the Mavs.
In Monday's win, Jefferson dunked three times, one more than three players did in all of last year.
He has made defense a priority again, often executing faultless rotations. As his teammates learn more of the schemes, his efforts will look better.
Popovich will expect him to perform numerous tasks in several hours—everything from neutralizing Howard to becoming another weapon Rick Carlisle must gameplan for.
The Mavs decided not to double-team Duncan or Parker in that first-round series, and it rendered Roger Mason Jr. and Matt Bonner useless.
How many open shots will they get against Dallas when they show up with a full compliment? Will anyone exhibit the patience to count past that first quarter?
The Mavericks also upgraded, and that fact is not lost here.
Shawn Marion will cause new headaches for Popovich, and no one should forget that he's one of the few, including Harris, who have given Parker consistent trouble.
With their patented Mavs-killer likely unavailable tonight, sophomore guard George Hill must do another reasonable impersonation of his French superior.
Popovich will ask Antonio McDyess to compensate for the help-defense and size lost with Duncan on the sidelines. McDyess will look for his shot more as will Mason, Bonner and Finley.
Manu Ginobili and Jefferson, however, are the keys to a victory.
This time last year, on Election Night no less, the Mavs spanked the Spurs in San Antonio, taking full advantage of Ginobili's absence.
Now, Manu returns with a vengeance and a new lethal weapon.
Jefferson knows this stint with the Spurs might be his final opportunity to win a ring.
He appreciates the effort required to reach the NBA Finals, and like McDyess, he says he has never recovered from losing in the championship round.
With apologies to the Raptors and Kings, the Mavs represent Jefferson's toughest challenge yet.
Mark Cuban didn't thrust his franchise deeper into luxury-tax territory for another second-round exit.
It will become much more difficult if Popovich again starts Jefferson at the four, as he did versus Toronto.
Even if he does not guard Howard one-on-one, the two will fill similar roles.
With Duncan and Parker benched, the victor of this matchup could determine who wins the game.
The Spurs hope Jefferson will emerge the hero.
Tonight and in May.