Raiders assistant coach Andrew Dunemann said the two players were being rested as a precautionary measure to ensure they would both be ready for their round one game against Penrith on March 10.
Dugan picked up a slight ankle sprain in last week's trial against Wyong/Mounties, while Wighton is still suffering from a hand fracture he picked up during the All Stars match.
"We want to make sure (Dugan's) 100 per cent right for that first game," Dunemann said.
"He's had a good off-season and we're pretty confident that we can rest him and he'll come back in round one."
Meanwhile, Shaun Fensom and Joel Thompson have both been included in the squad after being rested last week.
"That rest last week would have done (Thompson) a world of good," Dunemann said.
"Really looking forward to him playing, he's become a bit of a leader in our team, so can't wait to see him out there with the boys."
The only other player in doubt for the upcoming trial is Matt McIlwrick who will be given until Thursday to prove his fitness.
Players in the longer-term injury ward include Jarrod Croker (knee: round 1-3), Hayden Crockett (knee: season), Glen Buttriss (ankle: indefinite) and Terry Campese (knee: indefinite).
Raiders squad: Sandor Earl, Joel Edwards, Shaun Fensom, Blake Ferguson, Jake Foster, Haydon Hodge, Jarrad Kennedy, Tom Learoyd-Lahrs, Edrick Lee, Josh McCrone, Matt McIlwrick, Mark Nicholls, Josh Papalii, Dimitri Pelo, Joe Picker, Michael Picker, Reece Robinson, David Shillington, Joel Thompson Dane Tilse Paul Vaughan Brett White Sam Williams.