Piastri has won three consecutive races for McLaren, where he and his teammate Lando Norris are trying to dethrone Max Verstappen from Red Bull, the F1 champion every year since 2021.
Piastri is the first McLaren driver to win three consecutive races since the late 1990s.
Mika Häkkinen did it with a victory to conclude the 1997 season and gains in the first two events of 1998.
Piastri has dug his advance on Norris at 16 points, while Verstappen is 32 points in Piastri.
Norris won his first Grand Prix victory last year in Miami, after two Verstappen victories on the circuit surrounding the Hard Rock Stadium.
Norris also won the Sprint race on Saturday.
Norris quickly wanted to dislodge Verstappen de la pole, but he got out of the track and lost four places.
Norris said that Verstappen had forced her to get out of the track and that he could do nothing else to avoid a wall, but F1 took no measure against Verstappen.
Norris took over but not before Piastri took control at the expense of Verstappen, in the 14th of the 57 rpm.
In the last laps, Norris managed to reduce the gap, but he could never catch up with Piastri and was content with second place, thus offering a double to McLaren.
The two pilots were almost 40 seconds ahead of George Russell (Mercedes), who finished third.
“It’s simply incredible, hard work,” said Piastri, about McLaren. I remember that two years ago, here in Miami, we were really the slowest team.
“Having won this Grand Prix with more than 35 seconds in advance is the fruit of everyone’s hard work.”
Verstappen finished fourth.
Alex Albon (Williams) finished fifth, Kimi Antonelli (Mercedes) sixth and Charles Leclerc seventh, after Ferrari ordered Lewis Hamilton to give way to his teammate in the last laps.
Hamilton finished eighth.
Carlos Sainz finished ninth for Williams and Yuki Tsunoda tenth with Red Bull.
The Canadian Lance Stroll obtained 16th place with Aston Martin.
