Lewis Hamilton believes that Max Verstappen's blistering launch off the grid at the start of Sunday's Dutch Grand Prix points to the significant gains achieved by Honda's power unit.
Verstappen enjoyed a flawless start that allowed the Red Bull charger to comfortably outrun his arch-rival to the first corner, and his lead only increasing thereafter.
Hamilton, whose own start was reasonably good, said that he was incapable of countering his rival's launch.
"He was a rocket off the start, he was gone," said Hamilton. "Literally nothing we could do to answer that. They’ve made a big, big step forward this year with their engine.
"You saw it last year, they weren’t the greatest with starts and I think they obviously have improved their power, just the whole power unit’s massively better this year on all aspects for them.
"Naturally [that helps] their driveability and their starts… they’re the quickest starters this year overall.
"So, we’ve got some work to do in lots of different areas."
Hamilton claimed that in addition to Red Bull's engine muscle, the outfit's RB16B had benefitted from an upgrade at Spa, although the washed-out event didn't give the Milton Keynes-based outfit an opportunity to showcase its gains.
Hamilton urged Mercedes to respond with an update of its own, a demand that might fall on deaf ears as the Brackley squad has reportedly switched the bulk of its development resources to its all-important 2022 car.
"They were so fast," said the Briton. "That's the quickest I think they have been all year.
"They put an upgrade on their car at the last race, and on Sunday you have seen the improvement they have made, so we have to do some work.
"We've got to bring something to be able to compete with them."
The seven-time world champion hopes that Monza – a low downforce environment - will provide Mercedes with a better opportunity to challenge Red Bull.
"We will be on lower downforce, and maybe we can be closer there, maybe," he said. "But… yeah, it’s going to be tough."
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