With their season-opener against premiers Penrith just 12 days away the Sea Eagles endured a rough night on the Central Coast with a trio of their stars picking up injuries.
Prop Martin Taupau lasted just two minutes against the Raiders, falling awkwardly as he tried to tackle Xavier Savage and jarring his back in the process.
Taupau hobbled from the field and appeared to be in plenty of discomfort when he appeared on the sideline dressed in his Sea Eagles polo shirt soon after.
Taupau forced from field early
Manly's forward stocks took a further blow just after half-time when Haumole Olakau'atu came reeling out of a tackle holding his right arm.
The 23-year-old was treated in-goal by a trainer as the Raiders lined up the conversion of Nick Cotric's try.
Dylan Walker was the third casualty, limping the field with a leg injury as the Raiders stormed back into the game and the heavens opened to dampen Manly's mood even further.
Olakau'atu suffers arm injury against Raiders
"Haumole is probably the worst of three, he subluxed his elbow, he's the biggest worry for round one," Manly coach Des Hasler said.
"Marty we took off for a precaution, it was his back, not his hip or anything. Dylan will be OK, it's his ankle but we weren't taking any risks."
With Josh Schuster expected to miss at least the first four rounds with an ankle and Olakau'atu in doubt Hasler said Karl Lawton and Andrew Davey are in the mix for the Panthers clash.
Having kept many of his big names away from pre-season trials in recent years Hasler chose to use pretty much a full-strength side against the Raiders.
"We had to give these guys a run because of the start we've got [against Penrith and the Roosters]. We've got a tough one," Hasler said.
"Last year we had a lot of off-season surgeries but this year we're in better shape."