To emerge on top, the Chiefs had to overcame an arduous travel schedule that has seen them traverse the southern hemisphere in the last fortnight. They also dealt with an opponent who once more displayed they're a valuable addition to the new competition and, to top it all off, the visitors faced a deficit with two minutes remaining on the clock.
But Weber's try saw the Chiefs complete their road-trip with two wins from two, vanquishing the bad memories from their home loss to the Lions the day before they left these shores.
That outcome didn't always appear likely as the Jaguares delighted their home fans with some brilliant rugby. Much of the pre-match focus concerned the Argentinians' powerful forward pack but, while it certainly impressed, it was in attack where the hosts really excelled.
They almost seemed allergic to kicking during an electric first half, in particular, moving the ball well through the hands, offloading in the tackle and showing intricacy and intent.
Unfortunately for the Jaguares, their relentless tempo also at times proved their undoing, with their determination to push a pass resulting in errors that allowed a Chiefs defence to bend without breaking.
And for all their attacking enterprise, the Jaguares eventually turned their pressure into points through more traditional means, perhaps to prove a puma doesn't necessarily change his spots.
The Chiefs' scrum was demolished until they substituted their entire front row in the second spell and the Jaguares looked to drive the lineout at every opportunity, crossing for the game's first try through Augustin Creevy.
But if the home side needed any reminder they weren't the only side on the park who possessed a dangerous attack, that came when the Chiefs struck twice in smart fashion to hit the front.
Sam McNicol and Damian McKenzie both displayed their side's threat and, after making almost twice as many tackles as their opponents in the first half, that threat became more severe after the break.
The Chiefs repeatedly showed an almost unmatched ability to break from deep in broken play, with James Lowe finishing a brilliant backline move to score his side's third. Unmatched, that is, except for by their opponents.
Because after Martin Landajo burrowed his way over, Matias Moroni finished a length-of-the field effort to cap one occasion when the passes did stick and send the home fans into raptures.
But those emotions lasted only so long as Weber completed a thrilling contest in appropriate style.
Jaguares 26 (Creevy, Landajo, Moroni tries; Sanchez 3 pens, con)
Chiefs 30 (McNicol, McKenzie, Lowe, Weber tries; Cruden pen, McKenzie pen, 2 cons)
HT: 14-13
