Canterbury's Adam Elliott is facing season-ending surgery after suffering a dislocated shoulder that will require several months recovery.
Elliott's impressive start to 2020 has been brought to a sudden halt by the injury, which came in a tackle on Rabbitohs prop Tom Burgess late in Sunday's 26-10 loss.
The Bulldogs are awaiting final confirmation of scans on the injury from Monday, but surgery and a lengthy lay-off are expected for Elliott.
The 25-year-old is currently off-contract and at a delicate stage in negotiations with both the Bulldogs and rival clubs.
As a result his long-term injury could not have come at a worse time for him or the club, with pressure again mounting after four straight losses.
English recruit Luke Thompson's expected inclusion against Brisbane on Saturday does at least loom as a silver lining to the Bulldogs' latest injury woes.
Thompson made the final call to sit out the South Sydney loss after pulling up sore from his first week of training at Belmore.
But he looms as a much-needed front-row reinforcement for the round nine trip to Suncorp Stadium after serving two weeks of quarantine in a Melbourne hotel following his early release from St Helens.
"We're pretty confident he will be right next week," Pay said after the loss.
"We'll see how he goes during the week but we're pretty hopeful.
"He's a quality player. If you put any sort of quality player in your footy team, they're going to help the team.
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"He's an international and he's from a very successful club over there. He'll bring a lot to the team."
Hailing from the same stomping ground as one-time Canterbury captain James Graham and sporting the same red hair, Thompson has impressed plenty at his new club in the past week.
His renowned speed is tipped to be extra beneficial against a desperate Broncos pack, while the 25-year-old's professionalism around diet and preparation also has Bulldogs officials convinced they've landed a marquee prop to build the club around.
Canterbury's effort against the Rabbitohs couldn't be faulted.
But falling short once more leaves Pay under pressure as his side slumped to a fourth straight loss to sit outright last.
The Bulldogs did well to hold Souths to an 8-6 lead despite defending most of the first half, but Pay was left lamenting a second-half slump, not for the first time this season.
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"There was a lot more commitment there tonight," he said Pay.
"The first half was really strong. I thought the 15 minutes after half-time really hurt us.
"There were some opportunities there to take, but we didn’t really take them. [But] you can’t doubt their commitment and effort."