During the 56-lap race at the Circuit of the Americas, Sainz and Riccardo were involved in several battles, the first of which occurred on the first lap.
Following a surprise Q1 elimination during a disappointing qualifying session in Turkey, the Australian was set to start only 15th.
Hamilton's Mercedes W12 has a new internal combustion engine (ICE) and exhaust, but he had already used up his allotted number of new ICEs.
Sainz was one of the stars of the Russian Grand Prix weekend, qualifying second and racing to third after taking the lead early on.
Witnesses at the Italian Grand Prix recalled Binotto and Leclerc arguing heatedly in the team garage earlier this month.
The Russian GP saw Lewis Hamilton become the first Formula 1 driver to notch up 100 wins, but that wasn't the only talking point of the race.
Hamilton's win re-establishes him as the championship leader, but Verstappen's drive reduces the Brit's lead to just two points.
Lando Norris is going through an incredible run of form at the moment as he earned pole position in F1 for the first time in his career.
Ferrari are nowhere near the championship picture, with Mercedes and Red Bull fighting it out for the constructor's championship.
Sebastian Vettel loses second-place finish in Hungary after he is disqualified for not having the minimum amount of fuel at the finish.