Balance problems blighted Jenson Button's after second practice for the Spanish Grand Prix.
"I'm not very happy with the balance, but I will be working overnight to try and improve it," the McLaren driver said, who added that attention during the morning was fixed very firmly on the new parts before he got the chance to start pushing more in the second session.
The 31-year-old nonetheless thinks it should be possible to get more speed out of the car on Saturday. He was very satisfied with his long run – in fact, it even exceeded expectations. The challenge now is to find a good balance between racing and qualifying.
With the data collected on Friday, the hope in the McLaren camp is that they can make further progress over the rest of the weekend. The drivers were also optimistic that Red Bull's lead will not be as great as it appeared today.
"Let's wait and see what tomorrow brings. It depends on which engine mode they were using," Button speculated.
"We just don't know. We could have something up our sleeve and they could have something up theirs. We'll see," he added cheerfully.
"I wouldn't say that we have seen everything yet," said Button.