In addition to Cooper's absence, the Reds were also without injured captain James Slipper, while back-rower Leroy Houston was ruled out before kick-off, prompting coach Nick Stiles to recall George Smith to the bench after initially resting the veteran flanker.
Senior stars Karmichael Hunt, Scott Higginbotham and Stephen Moore stepped up at Estadio Jose Amalfitani, but were ultimately unable to stop the gallant Reds from suffering their fourth defeat in a row - and 11th straight loss on the road.
After a promising opening, Queensland's troubles began in the 18th minute when Nabuli was yellow-carded for a deliberate knock down as the Jaguares attacked from close range.
It appeared the winger was merely attempting a strong ball-and-all tackle to nullify a defensive overlap.
Then, in what looked another tough call, Wallabies lock Douglas received his marching orders for disrupting a driving maul from the ensuing Jaguares lineout win.
"Doesn't need a warning when it's cynical," the referee said after leaving the Reds seriously stretched for 10 minutes.
With Queensland reduced to a seven-man scrum and also short in the backline, the Jaguares centre Jeronimo de la Fuente stormed through a gaping hole in Queensland's defensive line to open the scoring.
The Reds looked to have restricted the damage to seven points until explosive winger Ramiro Moyano stepped and accelerated his way to a brilliant 50-metre solo try in the 28th minute.
Jake McIntyre and Juan Martin Hernandez traded late first-half penalty goals to leave the Reds trailing 15-3 at the interval.
De la Fuente's second try early in the second half, converted by Hernandez, extended the Argentines' lead to 22-3 before the Reds threatened a late fightback.
Higginbotham's 34th Super Rugby try in the 57th minute pulled the deficit to 14 points with ample time on the board.
Alas, the Reds were unable to add any more points despite enjoying all the running late and with the Jaguares themselves down to 14 men after winger Felipe Ezcurra was also sin-binned for a deliberate knock down.