Haas hobbled off midway through the first half at Campbelltown Sports Stadium with a suspected medial ligament injury and now looks set to join Reece Walsh, Billy Walters and Ben Hunt in the Red Hill rehab room.
A prolonged period without Haas would be damaging for reigning premiers Brisbane (4-3), who claimed a gritty victory on Saturday night courtesy of a late field goal from halfback Adam Reynolds.
"I think Payne's got a few issues with his knee, I'm not 100 per cent sure," said Broncos coach Michael Maguire.
"That's four weeks maybe, I could be making that up but it's up to the doctors.
"He'll go for scans and probably have a bit of time on the sidelines."
Haas' fitness will also be of concern for NSW coach Laurie Daley with a little over six weeks until the State of Origin series opener on May 27 in Sydney.
If Daley were looking for a ready-made replacement then Tigers prop Terrell May delivered a strong audition in a game where he chalked up 188m and made five tackle busts.
May was exceptional in a Tigers side that ultimately failed to capitalise on a dominant opening 20 minutes against a depleted Broncos outfit.
Maguire described the win as one of the most satisfying of his coaching career after stand-in fullback Jesse Arthars also went off and centre Kotoni Staggs soldiered on with a foot issue.
Reynolds was exemplary after Haas went off in the 34th minute, showing all his experience to set up winger Deine Mariner with a crossfield kick and hit Ben Talty with an inside ball close to the line to give the visitors an 18-14 halftime lead.
"He (Reynolds) knew he had to stand up for the group and he did that really well," Maguire said.
"I think the calmness amid what was going on… the players credited him after the game for how he held things together."
Hooker Api Koroisau put the Tigers back ahead early into the second half but two errors under the high ball from teenage winger Heamasi Makasini opened the door for Brisbane.
On the next set, Koroisau gave away a penalty for not being square at marker with Reynolds nudging a penalty to tie up the scores.
The veteran halfback then snapped a 70th-minute field goal to seal victory and end the Tigers' three-match winning streak.
"It's a learning curve... we've been up for so long now you guys can stop talking about us," said Tigers coach Benji Marshall.
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