Damian Blanch scored a brace of tries on his debut for Wakefield as they beat the Grand Final winners Leeds 26-18 in their Boxing Day friendly.
It proved a losing start for new Rhinos coach Brian McClennan, who was missing his seven Great Britain internationals.
Wakefield led 16-0 after the first quarter and withstood Leeds pressure in the second half to hold on for victory.
Elsewhere, Warrington lost 38-18 to Leigh while newly promoted Castleford drew 24-24 with Featherstone Rovers.
Irish international Blanch, who moved from Widnes to the Wildcats in the close season, notched his opening score for his new club after Sam Obst had put them in front.
Stand-off Scott Grix then followed up a grubber kick from Danny Brough to extend John Kear's side's advantage.
Leeds, led by hooker Matt Diskin, hit back through young wingers Ryan Hall and Danny Williams but Blanch went over for his second try in the corner with Brough adding the extras.
Ryan Bailey and Jamie Thackray tried to push forward for Leeds but the Rhinos only had a try from prop Michael Haley to show for their efforts.
The Wildcats made sure of the win when centre Ryan Atkins won a kick-and-chase to notch his side's fifth try but Leeds had the final say when Hall went 90 metres for an interception try.
Warrington fielded a youthful line-up against a near full-strength Leigh outfit but did include established first teamers in captain Lee Briers, Kiwi prop Paul Rauhihi, Chris Bridge, Ben Westwood and Rob Parker.
But Leigh, who led 22-6 at the break, were good value for their victory with winger Dave Alstead grabbing a superb hat-trick of tries and second row forward Lee Doran touching down twice.
The Wolves tries came from Andy Bracek, Lee Briers and Chris Riley.
Meanwhile, ex-Wakefield and Salford prop Michael Korkidas scored a try and helped set up another for fellow Castleford debutant Tom Haberecht against Featherstone.
Half-backs Anthony Thackeray and Joe Westerman also collected tries for the Tigers whose line-up included eight of their first-team squad.
Ex-Castleford full-back Tom Saxton grabbed two tries on his debut for Featherstone.