Button and teammate Kevin Magnussen managed just six and seven laps in the first practice session, as both suffered engine problems.

Magnussen crashed after four laps in the second session, while Button managed 21 on his way to the 13th fastest time, out of 16 cars.

Button said McLaren was currently some 2.5 seconds off the pace of the cars chasing leading team Mercedes.

"I am hoping it won't be the last row of the grid. Hopefully 20 cars will run," said Button of his qualifying hopes.

"It won't be easy and we all know it. We are all working as one and we are not pointing any fingers. We are just solving the problems as we go.

"Hopefully we will be competitive sooner rather than later."

When asked if McLaren needed reliability or performance, Button said: "I think we need a bucketload of both right now."

The Briton admitted the situation made it impossible for him to set goals for the weekend.

"I have no goals in terms of position," he added. "The important thing is to make sure we maximise everything we have and then look at timesheets in qualifying and the race, see how we fared, and how much work we have to do."