Tonga threw down the challenge with their pre-match haka but Lebanon weren't intimidated as The Cedars walked towards the Tongans as they eyeballed each other.
The crowd roared every time Cowboys lock Jason Taumalolo got his hands on the ball and he responded with bullocking runs towards the Lebanese defenders.
But despite coming into the contest as $12 outsiders, Lebanon refused to back down and didn't seem overawed by the occasion with a semifinal spot on the line.
Halves Mitchell Moses and Robbie Farah guided their team around the park, while veteran Eels prop Tim Mannah got through the grunt work up front.
Tongan coach Kristian Woolf praised his side's improved defence ahead of this game and they were tested regularly.
Woolf won't have been pleased to see his team leak 16 points during the opening 40 minutes but they did take a 22-16 lead to the split.
Having opened the scoring early through Tigers standoff Tuimoala Lolohea, David Fusitua added a double, alongside a four-pointer to Will Hopoate.
Hopoate was elusive throughout the game with his powerful fend and was one of Tonga's best.
Tonga were without prop Sio Siua Taukeiaho, scratched due to a knee complaint.
Woolf suggested after the captain's run yesterday that the Roosters forward would be good to go but he didn't recover in time.
His absence handed a start to Broncos big bopper Joe Ofahengaue, while halfback Ata Hingano took over the goal-kicking duties.
To their credit, Lebanon hung around and they were unlucky to have a try disallowed in the early stages of the second half, which could have seen them draw level if the goal was successful.
It was a mark of respect towards Lebanon that Tonga kicked a penalty in the 53rd minute, rather than search for a try.
That eight-point advantage proved valuable though as it kept The Cedars at arm's length and when Moses bombed a try only minutes later, Lebanon looked like they were up against it.
Abbas Miski completed his brace as Lebanon drew within two with only 10 minutes left but Tonga held on - just.
Tonga's kicking game let them down during the second spell and they will need to be better when the pressure ramps up further in the semis.
Every Tongan from the wider Canterbury region appeared to make it along for the game draped in red and with flags in hand as the crowd numbered 8,309.
The Tongan crowd support has been a feature of the tournament and that will further be on display in next weekend's semifinal where they will look to continue their dream run at the tournament.