A Jennings hat-trick spearheaded the Roosters' 36-14 World Club Challenge win over Wigan on Saturday at Allianz Stadium.
The NSW centre, who bagged the premiership-sealing try in last year's grand final, scored two first-half four-pointers to take the Roosters to an 18-0 halftime lead.
And with the visitors trying desperately to fight back in the second stanza, Jennings scored again to put the Roosters ahead 24-4 at the 49-minute mark after a Joe Burgess try opened Wigan's account in the 44th minute.
In an exciting, at times error ridden, encounter before 31,515 fans, the Roosters dominated the first half from the outset after Jennings palmed off Josh Charnley and raced 25m to score.
Sam Moa crashed over in the 13th minute after Jake Friend threw a face ball across Jared Waerea-Hargreaves close to the tryline, before Jennings pounced on a loose ball in the in-goal following a Matt Bowen fumble for a three-tries-to-nil lead that remained until the break.
With Wigan gaining more possession in the second half, the game became more of a contest and, after two tries to Charnley, the northerners had bridged the game to 24-14 after 60 minutes.
But the Roosters again took control of the contest to round out the match with tries to Waerea-Hargreaves in the 67th minute and Shaun Kenny-Dowall in the 71st minute.
Eddy Pettybourne was lucky to stay on the field after a high hit on Kenny-Dowall late in the first half, while a late shoulder charge from Michael McIlorum on Mitchell Pearce after a kick earlier in the game could have also resulted in an early shower.
Roosters coach Trent Robinson was pleased with his side's effort but described the win as "a bit clunky".
"We were physical but we lacked execution, that's normal this time of the year.
"There were some good parts and some awkward parts.
"We have better football ahead of us.
"For the most part we defended well.
"The most pleasing part was that we are physical. We went after them.
"I think they felt the pressure for a lot of the game."
Wigan coach Shaun Wane could see few positives in his side's performance.
"We were poor, the best team won. They are the world champions.
"When you complete at 67 per cent you don't give yourself a chance to win.
"We undersold ourselves out there.
"We didn't give a good account of ourselves.
"It's definitely hard to beat a team like that when you play like that."
