The Australian was forced out before quarter distance to become the race's first retirement.
It was a disappointing end to the weekend, doubly so for the team as Lando Norris had a pneumatic leak that forced him to pit on six occasions.
“The start of the race, and the grid procedure, I think someone in front of me stopped in the wrong box; I don't know if it was Logan [Sargeant] or someone else, but it was a bit of a last-minute move into the correct box,” Piastri began when asked by Speedcafe.com about his first race in F1.
“It all happened pretty quick, but [my] launch was really good; didn't get the cleanest run into Turn 1 with [Yuki] Tsunoda but thought my first lap was reasonable.
“After that, [I was] sort of in the DRS train, not being able to do much until some other people had some tyre deg, and then managed to pass [Nico] Hulkenberg.
“All in all, I think a lot of boxes ticked from the start and obviously was clean myself, so I think it was positive.”
Piastri headed into the race having not raced for a year and predicted that rustiness would materialise. However, there was little indication of that prior to his retirement.
That came on Lap 13, though the Melburnian revealed the writing was on the wall a handful of laps earlier.
“I would say probably started, I would say, a couple of laps before I stopped,” he explained of the electrical fault.
“Just a few things flashing up on the dash that were a bit unexpected.
“Then it started messing with the gear shifts and stuff like that. So obviously, not ideal.”
McLaren boxed the 21-year-old and in the first instance changed his wheel but that failed to resolve the issue.
“It wouldn't fire up,” Piastri recounted.
“I'm not 100 percent sure what was wrong. We thought it was the steering wheel based on what was happening, but it wasn't, so we'll diagnose what was wrong.”
The F1 season continues with the Saudi Arabian Grand Prix on March 17-19.