The governing FIA had reported both drivers to stewards after their cars failed post-race checks on the under-floor wooden planks at Austin's Circuit of the Americas (COTA).

Stewards imposed the standard penalty after both teams acknowledged the measurements carried out by the FIA were correct.

Mercedes had stated that the high wear on the skid pads was probably due to the bumpy track and the race being run to a sprint format for the first time.

That meant a 100km race on Saturday and only one practice session instead of the usual three.

"Set-up choices on a sprint weekend are always a challenge with just one hour of free practice, and even more so at a bumpy circuit like COTA and running a new package," said Mercedes principal Toto Wolff.

"In the end, all of that doesn't matter; others got it right where we got it wrong and there's no wiggle room in the rules.

"We need to take it on the chin, do the learning, and come back stronger next weekend."

The race was won by Red Bull's Max Verstappen, the 50th victory of the triple world champion's career and a record-equalling 15th of the season.

Mercedes had brought an upgraded car to Texas and Hamilton, whose team-mate George Russell moved up to fifth, had looked more competitive.

"We can take a lot of positives from the car performance today," said Wolff.

"This is a circuit where only a few races ago we wouldn't have performed well because of the fast, sweeping corners. The upgrade seems to have made the car happier in those areas and it is working well. Directionally, it's a very good sign."

The disqualifications meant Leclerc's team-mate Carlos Sainz moved up to third.