Stoffel Vandoorne described German Grand Prix practice as his “worst Friday for a long time” as he slumped to last in both sessions.
McLaren brought updated parts, intended for use at future events, to Hockenheim, with both Vandoorne and Fernando Alonso trialling the components early on.
But Vandoorne finished last of the 20 runners in the opening session, a position he replicated later in the afternoon, three spots and six-tenths of a session down on team-mate Fernando Alonso.
It comes two weeks after Vandoorne struggled for pace throughout the British Grand Prix weekend, where he was ill at ease with the feel of his MCL33.
“In the afternoon, we again had a difficult session,” said Vandoorne.
“This has probably been my worst Friday for a long time – I had a similar feeling to what I had at Silverstone, that something isn’t working properly on the car.
“We can see that the car is not in its normal conditions, and at the moment it’s a bit of a question mark for us to firstly put the car back to a position where it behaves normally, and then to see how we’ll get on, on Saturday.
“There’s going to be a lot of data analysis tonight to understand how to get the car back in normal conditions for tomorrow, and we’ll probably change quite a lot of parts on the car.”
Alonso believes McLaren’s position in the leaderboard, having placed 12th and 17th in the two sessions, is not reflective of its actual ability.
“We tested a lot of things today and we probably compromised our final positions because of that,” he said.
“We have been in quite a good place on Friday in the last couple of races, and it’s a matter of fact that with two or three tenths you can lose or gain a lot of positions.
“Here in Hockenheim we’ve lost a few positions.”
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