Scotland winger Duhan van der Merwe, one of the most physical players in Europe, said: "I've never been hit like that before", after being relentlessly smashed, mostly legally.
However, Number eight Vaea Fifita was shown a late bunker upgraded red card for a wild assault on Finn Russell at a ruck in the closing minutes.
And winger Afusipa Taumoepeau looked extremely lucky not to have his yellow upgraded after his shoulder charge into the head of Jamie Ritchie, which ended the Scotland captain's involvement after 34 minutes.
“It is natural for us (to be physical in the tackle)," coach Toutai Kefu said. "I think when we defend for long periods, it takes a bit of juice out of us and we become a little inaccurate. It is not intentional.”
Tonga looked far better for much of the game than in their 59-16 defeat by Ireland, scored two nice tries and disrupted the Scots for long periods but somehow managed to miss 45 tackles.
"The difference between our first two games is we got some ball to fire some shots today," said Kefu. "We took some opportunities, scored some tries, probably missed some opportunities as well.
"But we weren’t able to put sustained pressure on them and missed a lot of first-time tackles. There were some really good defensive sets there. It was a much better effort compared to last week.
“We have to learn to hold on to the ball, we lost possession and territory, and that put us under sustained pressure. We let in some easy tries but we are tracking in the right way."
Captain Ben Tameifuna delivered the now-familiar lament of the tier-two system of nations about their preparation struggles.
"It shows what it takes to play against tier-one teams," he said. "Our build-up has been against tier-two teams and below. The pace is faster, which we have to adapt to."