Bahrain Friday 'best day' in years for McLaren-Honda says Button

Button starred in the second practice session on Friday, finishing best of the rest behind Mercedes pair Nico Rosberg and Lewis Hamilton.

The result is comfortably the highest McLaren-Honda has been since the two parties reunited in F1 last year, and Button was buoyed by the fact it was on merit, rather than as a result of changeable conditions.

"It's nice to have a car that feels good underneath me and we can really work with and see good gains," he said.

"I think when you look at how far we were off the Mercedes, that's the time you've got to gauge, really. That's 1.2 seconds.

"I think there will be cars that slip in between us tomorrow, but you've got to say that it was a good day for us, and it's been the best day for a couple of years."

While Button was 14th in the opening session, he feels the car would have been "equally competitive" with high fuel in the opening 90 minutes, if his second run had come together.

Noting that reaching Q3 on Saturday "has to be the aim", he admitted more work is needed on longer runs.

"The balance is reasonable," he said.

"The car's feeling nice around here, definitely better than Melbourne.

"High-fuel runs weren't too bad either, there is a bit of work needed, especially on the back-up [medium] tyre.

"But on the super-soft, it's working reasonably well.

"There's certain areas we need to improve, and I think we still can improve."