Lewis Hamilton believes Mercedes' upgrades have made the Formula 1 car slower as he qualified behind his teammate in the old version at the Mexico City Grand Prix.

Mercedes once again experienced a disappointing performance in qualifying as neither driver was able to challenge their main rivals as George Russell finished fifth and Hamilton sixth.

Hamilton was almost three tenths behind Russell in the third quarter, despite being the only Mercedes driver with the updates introduced by the team in the USA.

The seven-time F1 champion chose to keep the new parts on his car, although he suspected the revised components contributed to his failure at the end of the race in Austin.

But while Mercedes boss Toto Wolff insisted there was no glaring problem with the developments, Hamilton is convinced the changes have brought no improvement.

“P3 felt decent. “It felt like we were on the right track,” Hamilton told the media Motorsport week in Mexico. “I have decided not to make any changes.

“We just put the wing on and I thought, 'Okay, let's leave it there.'

“We couldn't change much in the setup to move the car forward. The performance is where it is.

“Then we got into qualifying and I wasn’t behind. It was like it had fallen on its head. It's a very strange thing with the car.

“It will be interesting to read the results because I'm obviously driving the updated car, which should be faster. But I don’t think it is.”

Hamilton has revealed that overnight tweaks to the setup were a step in the right direction until the switch to a heavier-duty rear wing on the W15 derailed the progress.

“We definitely took a good step in FP3, at least in terms of balance,” he explained. “But with the actual car we were still six tenths behind the cars in front of us.

“We installed the larger wing to get more downforce and just drove slower.”

Hamilton confused by snapshots of Mercedes cars

Meanwhile, Hamilton reiterated that this weekend he was still feeling the “tricycle” feeling that he experienced during his spins last weekend.

When asked if he had any idea why the car broke down, Hamilton replied: “Not really.

“We have tricycles and the ride height moves up and down 15mm and when that happens, that’s basically awesome.”

Hamilton is expecting a tough race

Hamilton reckons it will be an impossible task for Mercedes to keep pace with the Ferraris and the leading McLaren and Red Bull cars in the race.

Asked whether the two cars with alternative specifications would provide a good comparison, the Brit added: “Tomorrow we will get a lot of data.

“I don’t think we can keep up with the guys in front of us. They’re just too far.”

“So just see how it goes. At least this time I want to reach the end of the race.”

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