The Australian took the flag in 10th following a switch from hard to medium tyres with six laps remaining.
It was a sharp improvement from his 18th place starting position that owed much to a decision to remain on track during a mid-race Safety Car.
However, while that call saw Piastri rise up the order initially, it ultimately sealed his fate later in the race.
“The timing of the Safety Car was pretty much perfect for the guys that stayed out on mediums at the start,” the McLaren driver explained.
“Look at Ocon, and it worked perfectly for him.”
Piastri had started the race on a set of the hard compound tyres, boxing on Lap 16 for a second set.
With F1 rules mandating the use of two different compounds, he was then compelled to stop for a second time.
However, while he gained track position from the mid-race Safety Car, the bunched field never spread out to a great extent, meaning he ceded much of it when he stopped in the latter stages.
“I was really wishing the rule of using two compounds didn't exist, because I would have just gone to the end on the hard,” Piastri said.
“I think we had the pace to hand on to people, so that was a shame.
“The pace of the car was a really good surprise,” he added.
“[Qualifying] obviously wasn't particularly representative of our pace, but today was probably better than we expected.
“So we need to understand what the difference was.”
Piastri energised the race with a series of overtakes, including a bold move on Pierre Gasly at Turn 5.
He also battled with Lewis Hamilton for a time, the pair picking up punctures as they made contact on Lap 16.
Piastri immediately recognised he was in trouble and dived into the lane for a fresh set of tyres.
“It was kind of just an awkward one,” he explained of his clash with the Mercedes driver.
“Neither of us had really committed to the corner that much and we both committed at the last minute.
“Then I was trying to back out of it, but we just ended up meeting in the middle.
“So I had a puncture from that.
“I don't think it really hurt our race in all honesty,” Piastri continued.
“Yeah, it would have been interesting to see if a one-stop could have worked.
“It's always hard to know. We would have been a sitting duck, like [Pierre] Gasly pretty much.
“A lot of things for a lot of people went wrong in that race, and I think I was in the same boat.”