Verstappen has retaken the lead of the world championship from Hamilton after being declared the winner of the rained-off Belgian Grand Prix and claiming a dominant victory at last weekend’s Dutch Grand Prix. 

Hamilton was pipped to pole by his main title rival by just 0.038s in Zandvoort and the Dutchman was able to rebuff Hamilton in the race as Red Bull maintained its pace advantage over Mercedes. 

The seven-time world champion suspects Red Bull has recently introduced another performance-related upgrade. 

"I think they’ve definitely improved their car with some sort of upgrade in the last race, which we didn't obviously get to see the true pace of it,” Hamilton said. 

"We’re trying as hard as we can. We had a couple of races where it looked like we were on par with them, or just slightly ahead, but there’s only been a couple of those, and then it took a big leap and it’s been difficult.

"I guess, it’s so close that you can’t really overtake in a lot of these places that we’ve been to previously because we are so closely matched. We just have to keep our heads down, keep working, keep pushing. 

“We are ahead in the team championship which is great but, of course, we need to pick up some speed. That’s what we want, to be able to win races in future.”

Hamilton described Verstappen as being a “rocket off the start” and conceded there was “literally nothing we could do to answer that” on the run to Turn 1 at Zandvoort. 

“They’ve made a big, big step forward this year with their engine,” he added. “You saw it last year, they weren’t the greatest with starts and I think they obviously have improved their power.

“The whole power unit’s massively better this year on all aspects for them – their driveability and their starts. They’re the quickest starters this year overall.

“We’ve got some work to do in lots of different areas.”