Lewis Hamilton scorched to a surprise result during Sprint Qualifying with Max Verstappen set to start third.
Piastri will line up third, just 0.08s off the absolute pace, in a session that promised more for the Australian.
“Probably quick at the wrong points,” he said.
“SQ1 and [SQ]2 felt good, and then SQ3 we tried something a bit different and went out much earlier and tried two laps, which I’m not sure was the best thing.
“It’s something we need to have a look at.”
Piastri had set the provisional pole lap with his initial effort in SQ3, but remained on track for a slow lap before a second push in the seconds before the chequered flag.
It was the same approach adopted by Mercedes, with the six other remaining runners staying in the garage until three minutes remaining.
That paid dividends for Verstappen, who rose to second, and Hamilton who needed just the one attempt to steal pole position.
It was an upset performance as McLaren looked set for top spot following an impressive opening practice from Lando Norris.
“It’s been difficult,” Piastri said of his Friday.
“With the track surface, it’s got a lot of grip but it’s very peaky.
“It’s been pretty tough all day just to keep on top of the car and, honestly, I think we did a good job of trying to tame it for Sprint Quali, just maybe got the run plan a bit wrong.”
While Piastri completed his second lap, and was unable to improve, team-mate Norris aborted his.
A mistake at the Turn 14 hairpin saw the championship leader run wide, ruining his chances of improving from sixth on the Sprint grid.
“I locked up in the last corner,” he explained.
“We just struggled a bit more now, just not quick enough.
“Our difficulties that we’ve been struggling with showed a lot more today, nothing more than that.
“Too many mistakes, but just too difficult of a car to drive.”
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Both Norris and Piastri had complained about the car’s handling during practice, with the MCL39 proving a handful at highs peed.
That has been a trait since pre-season, where the car proved rapid but lively in Bahrain.
“We’ve been struggling a bit with the front locking and struggling a lot in the last corner with all the tail winds,” Norris explained.
“Both myself and Oscar struggled, clearly me more than him.
“I can’t make the car perfect,” he added.
“This was me just trying to push a bit too much.
“The car is still in a good window, maybe not good enough for pole, but we can definitely go forward.”
The Chinese GP Sprint begins at 14:00 AEDT tomorrow ahead of Qualifying for Sunday’s race at 18:00 AEDT.
2025 F1 Chinese Grand Prix – Start time, how to watch, TV times & more
