The Renault man was given the penalty for exceeding track limits and gaining an advantage on the first lap.
He had started P11, but immediately made his way past several cars in the first corner. He went on to finish in P7 in Austin.
The Spaniard served his five-second penalty at his only pit stop, but Haas boss Guenther Steiner thinks the stewards took too long to react.
“Our team manager will bring it to the Sporting Working Group,” Steiner said.
“You cut the corner, take an advantage, and then it takes five laps to realise that somebody did something, it takes another five laps [to make a decision] – and you are gone by then because everybody’s stuck.
“Then they give you five seconds, which means nothing, because you’re gone. It’s wrong.”
The Austrian believes that sometimes it can be used to the drivers’ advantage, especially on the first lap.
“If you’re clever enough, and some people are clever enough to play this as a strategy, just cut it [the corner] knowing that you get five seconds, and try to drag it out,” he added.
“Because on the first lap there are so many incidents, and the stewards deal with the incidents on importance. For sure the front [of the field] is more important.
“If you would replay this race and [Carlos] Sainz was put back in the position where he started, the race would have developed completely differently.
“I think nobody thinks about this because nobody really cares, but we should care.”
Force India team principal Otmar Szafnauer also felt aggrieved, saying the penalty was not harsh enough.
“Sainz ran wide and gained an advantage,” Szafnauer said.
“He braked really late, and the fact that he went off the track to overtake everybody, and he got a five-second penalty, isn’t really commensurate with what he did.
“It’s not in line with the regulations. It should have been a stop-and-go or 10 seconds if he doesn’t give the place back.”
Despite the moans and groans, FIA race director Charlie Whiting insisted that the penalty dished out by the stewards was correct.
“When you have the sort of situation you had in Abu Dhabi last year, where Nico Hulkenberg overtook, knowing that a five-second penalty would be the likely penalty,” Whiting said.
“He easily gained more than five seconds so it was worthwhile doing – that’s why we’ve issued a new set of guidelines to the stewards.
“The teams are aware of it, where if we think it’s being done deliberately, they will take a wholly different view.”
However, the stewards did not see what Carlos Sainz did at COTA as deliberate, and more just a typical first lap kind of thing.
“But on the first corner of the first lap [at Austin] it was a bit of a muddle up there, and it was quite clear he went up the outside of [Charles] Leclerc, and then went around and went very wide,” he continued.
“It looks as if he followed Sebastian [Vettel] a little bit, and then he came back on and was in front.
“I think you have to say he gained an advantage by doing that.
“But as far as the penalty is concerned, I think it’s the standard penalty.”