New team principal Andrea Stella and McLaren Racing CEO Zak Brown admitted that 2022-23 winter development targets had been missed when the MCL60 challenger was launched.
The car duly failed to score a point across the opening two weekends but, led by a three-stage major update package, emerged as the most credible and consistent challenger to Red Bull.
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Speaking exclusively to Autosport, F1 rookie Piastri - who won the Qatar Grand Prix sprint race - reckons the speed of the 2023 revival surpassed what anyone had predicted.
“I've got complete confidence in [Stella], in Zak, in different parts of the business," he said.
“It's exceeded everyone's expectations of how quickly we've been able to turn things around.
“For me, the impressive thing was I felt there was a very good base with the race team at the races. And then when we needed to make changes, we did, and it's worked.
“The upgrades were able to deliver everything we hoped, in some cases more than we expected in certain situations. I didn't expect to be in this position so early in my time at McLaren…
Source: Autosport