Payne Haas will be sent for scans on a knee injury after the NRL's premier prop failed to finish Brisbane's 21-20 win over Wests Tigers.
Haas hobbled off midway through the first half at Campbelltown Sports Stadium and looks set to add to the Broncos' sizeable injury list which includes Reece Walsh, Ben Hunt and Jesse Arthars, who limped off after halftime with a calf issue.
A prolonged period without Haas would be devastating for reigning premiers Brisbane (4-3), who were steered to victory on Saturday night by halfback Adam Reynolds.
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.
If Daley were looking for a readymade replacement then Tigers prop Terrell May made a strong audition in a game where he chalked up 188m and made five tackle busts.
May was exceptional in a Tigers side that failed to capitalise on a dominant opening 20 minutes against a depleted Broncos outfit.
Adam Doueihi converted Taylan May's opening try in the ninth minute and then kicked a penalty goal to put the home side ahead.
Brisbane returned serve when Xavier Willison made a run up the middle and looked to have been contained by Api Koroisau.
But the Broncos prop played on and Ezra Mam was able to fling the ball to left wing for Josiah Karapani to slide over.
Haas got up gingerly after a tackle involving Royce Hunt and tried to soldier on, but came from the field in the 34th minute after the Tigers had extended their lead through Jahream Bula.
Reynolds then showed 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.
Koroisau finished a flowing move to nudge the Tigers back ahead 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.
The veteran halfback then snapped a 70th-minute field goal to seal victory and end the Tigers' three-match winning streak.