Scans confirmed on Friday that Paulo had suffered a lisfranc injury in his foot in Thursday night's 32-16 loss to South Sydney, ruling the prop out for eight weeks and almost certainly ending his season.
The news came as interim coach Trent Barrett turned the heat on his players for being the architects of their own downfall, with the Eels back at the bottom of the NRL ladder.
The defeat - the club's fourth in a row - came after a week in which it emerged that star halfback Mitchell Moses had unloaded on his teammates and the club hierarchy in a post-match tirade after the previous week's loss to Newcastle.
The Eels have just one win to their name since axing Brad Arthur, with the club's next permanent head coach yet to be determined.
Dean Young, Jason Ryles and Josh Hannay are the final three contenders for the role, and while Barrett has made a pitch for the gig, his 1-5 record since stepping in as caretaker is unlikely to strengthen his case.
Interim coach Trent Barrett has managed just one win in six matches in charge. (Joel Carrett/AAP PHOTOS)
Parramatta's board met this week, but an announcement is unlikely to come until next week.
Paulo's injury adds fresh angst for the Eels, who will finish the year with Moses, Paulo and Clint Gutherson all on the field together in only eight of 24 matches.
Moses' frustration was clear again on Thursday night, sin-binned late in the game for a professional foul after the Eels had chances to steal the match.
Camped on Souths' line for much of the first half, the Eels clawed back to within a converted try, before allowing the Rabbitohs to cross just before the halftime siren.
"There's nine seconds to go and you can't do that, we need to be more desperate there," Barrett said.
"At 26-16 at the end it's respectable, and you let in another ordinary try and it blows out to 30 and you think, 'they've been walloped again'.
"It's not the case, but we've got to get that out of our game.
"We were too sideways (with the ball)… you won't score pretty tries in the wet.
"The tries that you're going to score off a kick or a drop or by playing through teams, they're still worth four points, they don't have to be beautiful, and we were probably guilty of that."
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