Lewis Hamilton says his Mercedes Formula 1 car feels "back to normal" in Japan following the struggles of the past two races in Malaysia and Singapore.
Despite Hamilton winning in the wet in Singapore and finishing second at Sepang, Mercedes had recently struggled to match the pace of chief rivals Ferrari and Red Bull, particularly in the previous race in Malaysia.
Hamilton had decided against racing the team's latest update package at Sepang, as he felt more comfortable with the old aero.
He switched to the new package for Friday practice at Suzuka and, after finishing second behind Sebastian Vettel in a dry first practice, he said his car felt competitive again.
"It's been an interesting day, the car is feeling much better than it was in Malaysia," said Hamilton.
"The car feels back to normal, so I'm ready to race."
Hamilton was quickest of the handful of drivers to do flying laps in the wet and truncated afternoon session.
"I'm glad that we had the dry session for FP1," he said.
"In FP2, there was a lot of rain, but it felt really important to go out and assess the track and see how the car was feeling as the car was not good in the wet in Malaysia."
Team-mate Valtteri Bottas also found the Mercedes to be stronger than in Malaysia, but reckoned there was still work to be done.
Bottas finished practice one down in fifth position, nearly a second off the pace, and did not go out in the afternoon session.
"The car did feel better than it did in Malaysia, but we still need to work on things to make the car quicker," he said.
"As a starting point for the weekend, it definitely feels better than a week ago.
"My run with the soft tyres was good, but with the super-soft, I didn't really gain any grip.
"So the main thing for me is to understand the super-soft performance.
"The long runs actually weren't too bad, and hopefully we'll see better weather tomorrow."