The Dutchman had a tricky afternoon from sixth on the grid, and had to overtake Lando Norris on track to claim the lead of the race.
Throughout the 56 laps, Verstappen was complaining over team radio about his braking performance, leading to several amusing exchanges with race engineer Gianpiero Lambiase.
Speaking to Sky after the race, Verstappen detailed what was wrong with his brakes in Austin.
“We changed the brakes after yesterday and it was not good,” he said. “I had no good feeling under braking and I couldn't really get on top of it for the whole race, so this is something we need to understand.
“Of course, around here when you are not very confident under braking, you just don't have the nice feeling under braking when you come off it. It can cost you quite a bit of lap time and it was a bit more difficult than I expected it to be.
“I normally never really struggle with braking so far in my F1 career, but it was definitely a bit of a problem.”
Verstappen also felt Mercedes could have won the race with Hamilton if “they did a better strategy”.
“For sure, they could have won today if they did a better strategy after the first stop. The whole weekend they were very quick,” he added.
“Today from our side, with the brake issues it was hampering my pace but in general they were very strong this weekend."