Tonga held off a stiff challenge from the USA to record a 22-13 win in the International Rugby Series at Colwyn Bay.
Will Helu and Robbie Shaw traded first-half tries as the game remained in the balance.
But Joe Tu'ineau's second-half score proved decisive before Sione Piukala sealed the win.
After laying down the gauntlet to the USA with an intimidating version of their Sipi Tau war dance, the Tongans backed up their initial intent with an early score.
The South Sea Islanders dominated the early exchanges and were rewarded when Helu crossed in the corner. Fly-half Fangatapu 'Apikotoa missed the conversion but a 5-0 lead was just reward for their fine start.
Unsurprisingly, the Tongans were immensely physical in the contact area, though the American forwards stood up to the challenge, their set piece holding its own.
Captain Todd Clever was the main sauce of American go forward ball, taking on the Tongan pack at every opportunity. With a platform in the opposition half, the USA looked like they had found a way back into the game but Luke Hume's score was ruled out for a forward pass from full back Zachary Pangelinan.
After falling behind early on, the Eagles were growing into the game and got their reward when Pangelinan got his side on the board with a long range penalty.
And they continued to pound away at the opposition line from the restart, their front five causing problems for the Tongan defence. Though they were frustrated initially, the Eagles finally got the reward their efforts deserved when scrum-half Shaw dived over under the posts.
Centre Paul Emerick provided the break, offloading to midfield partner Andrew Suniula. Tackled just short of the line, he popped the ball up to Shaw who scored with ease. Pangelinan added the conversion with the last kick of the half to give his side a 10-5 interval lead.
The full back kicked a penalty soon after the restart but Tonga's Vungakoto Lilo responded for his side as the game remained in the balance.
After struggling for most of the first-half, Tonga were now revived and lock Tu'ineau crossed after Helu and held off a number of American tacklers. Apikotoa converted and Tonga led 15-13.
And they made sure of the win when Piukala crossed late on.
Nearly 40 players were involved in the first Wales Under 18 training session of the season. WRU National Performance Manager Gethin Watts is excited at the potential shown by the group and expects the Regional Under 18 Championship to hone their skills even further.