Championship leader Francesco Bagnaia said on Thursday he expected an intense battle at this weekend's Indonesia MotoGP to stay at the top of the standings, with rival Jorge Martin only three points behind.

Martin, of Ducati satellite team Pramac, reduced the Italian's lead with six races left after winning a Japan MotoGP cut short by rain this month.

"I think we can be competitive. The fight will be intense," Ducati's Bagnaia, 26, said before the race at Pertamina Mandalika International Circuit.

"I feel good honestly, I think all the races in front of us are good for me," he told a news conference.

The Spaniard had already narrowed the gap in the previous race in India after his rival catastrophically crashed out just over halfway through the race.

"We are so close now in the battle. I think my mentality will be the same, trying to win, trying to win races," he told reporters.

"Hopefully we can keep the momentum."

The crash in India wasn't Bagnaia's first of the season, having come off at high speed at the Catalunya MotoGP at the start of September in a pile-up that also injured Italy's Marco Bezzecchi.

The race will be just one of the few left at Honda for six-time world MotoGP champion Marc Marquez after it was announced on Thursday that he will join Ducati satellite team Gresini Racing for the 2024 season.

"It has been a super difficult decision. It was a little bit hard on the personal side because all my staff, all my friends, all my family are there," he said.

Marquez said he made the decision last week to give Honda more time to deal with his exit and said he moved to enjoy his racing again.

"The easiest way was to stay in Honda... but if I want to take care of myself and my career, I need to find a new challenge," he said.

His rival Martin said he believed Marquez would "be battling for a championship for sure" after the move.

Bezzecchi, third in the standings, said on Wednesday he hopes to ride in this weekend's race a week after undergoing surgery on a broken collarbone, calling it a "race against the clock".

MotoGP returned to Indonesia last year for the first time since 1997 at a new venue on the resort island of Lombok.