A minute's silence was impeccably observed by the 21,935 crowd at Ausgrid Stadium for tragic Tiger Mosese Fotuaika, who passed away recently, and it appeared to inspire Potter's side early in the game.
However, the Knights, inspired by Uate and two former Brisbane Broncos in Darius Boyd and Gagai, took control to effectively seal the victory before halftime.
Ex-NSW winger McManus dived over in the 10th minute after hauling in a fine cut-out pass from Boyd and the Queensland star looked to have increased the advantage only to spill the ball as he crossed the line.
But that proved to be a minor aberration when Uate, fresh from signing a new four-year deal, started and finished the move for the second four-pointer.
The Blues star caught the ball on his own 10-metre line, shrugged off three feeble tackles as he raced 50 metres and was then on hand to pick out Gagai's pass to go over in the right corner.
Gagai then scored two quickfire tries with skipper Kurt Gidley kicking four goals to open up a 24-6 lead at the break.
The second stanza followed a similar pattern with the Knights dominating as the Tigers fell apart, giving up two more Uate tries within nine minutes of the restart.
McManus added his second just before the hour-mark when he outjumped the diminutive Matt Utai and grabbed Jarrod Mullen's kick with Gidley's conversion bringing up the 40-point mark.
Tim Moltzen stretched to score on the siren to give the Tigers a late consolation.
The Knights' promising start was tempered by an wrist injury to Mullen, who went off midway in the second period.
Knights coach Wayne Bennett said he was pleased with his side's performance but said it was important no one got carried away by such a positive start to their campaign.
"There may be people looking over their shoulders, but I wouldn't say it was a statement," Bennett said.
"The first thing we have to do is not look ahead too far to Manly next week.
"We need to look at ourselves, get over our bumps and bruises and then we'll worry about Manly later in the week."
The veteran coach also said the injury to Mullen was not serious and that he withdrew his five-eighth as a precaution.
"I wanted to give Tyrone Roberts a bit of time out there that was all, but there is no problems with Jarrod," he said.
The defeat was a miserable start to Potter's reign at the Tigers and when asked if he had any words of encouragement for his opposite number, Bennett merely said "welcome!"
Potter said his side needed to improve fast before this week's clash with Penrith at Campbelltown.
"It was disappointing, in a lot of areas we could have done a lot better, but the scoreline doesn't read very well," Potter said.
"Early, everything was going to plan, but we slowly deteriorated and came up with errors and gave away silly penalties and a lot of possession.
"You can't do that and expect to win games."
- AAP
