A concerned Jos Verstappen says his son's team, Aston Martin Red Bull Racing, has made no progress since the summer break, insisting the RB15/Honda package is now trailing front-running its rivals by half a second.
Over the summer, two wins - in Austria and in Germany - allowed Max Verstappen to become the only driver to defeat the mighty Mercedes squad. But since Spa, the Dutchman and his team have been shut out from the lead battle between Mercedes and Ferrari.
In Russia last weekend, Verstappen qualified fourth, over half a second adrift from poleman Charles Leclerc, and finished in the same position, some 14 seconds down on the day's winner, Lewis Hamilton.
"We should have been closer, but that is more difficult than we thought," Verstappen Sr. told Ziggo Sport's Peptalk.
"It is very frustrating. In the last races before the summer break it went really well, but after the summer break we did not progress while the other teams did.
"Max cannot change that, we depend on the team, the car is a bit behind, the engine is a bit behind, more work has to be done on this combination if we want to challenge for the world title next year."
©RedBull
Jos Verstappen questions whether Red Bull can improve its performance in the short-term.
“We are very concerned if there will be any improvement in the short term, we will talk to the team to see what can be done," he added.
"We depend on the equipment we get and at the moment it is not good enough."
Judging by the former F1 driver's comments, frustration is clearly growing in the Verstappen camp.
"Seeing Max’ performance, put him in a good car and he will challenge for the world championship," said the 22-year-old's father.
"We are now working with Red Bull for a couple of years, but it still does not look that we will be able to challenge for the world title next year.
"Looking at the last couple of races it seems that we will be half a second short in Japan.
"Of course we will try everything to close the gap, but half a second you cannot catch up in two weeks’ time.
"The expectation was to close the gap to the competition, but at the moment it does not look like it. We have to work hard to close the gap, otherwise next year will be lost too."
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