Jorge Martin took a major step towards his first MotoGP world title as he won the sprint race in Malaysia on Saturday and rival Francesco Bagnaia crashed out.

Spain's Martin extended his championship lead to 29 points from 17, with just the grand prix on Sunday at Sepang and one more race weekend to go.

It was a bitter blow for Italian two-time reigning champion Bagnaia, who started on pole but came off his Ducati early on to gift a big advantage to Martin.

Pramac Ducati's Martin romped home nearly a second ahead of six-time world champion Marc Marquez and can seal the title on Sunday if he earns nine more points than Bagnaia.

"I think last year I wasn't ready to win," said the 26-year-old Martin, who came second in the title race behind his rival last year.

"This season I am more mature. It is a privilege to be here at this point with this advantage, but nothing is over till it's over."

Light rain fell at a sweltering Sepang five minutes before the start of the 10-lap sprint, adding to the tension on the grid.

Bagnaia started on pole with Martin alongside him on the front row, only for the Spaniard to seize the lead at the first corner.

With eight laps to go and pushing hard, Bagnaia lost control of his Ducati at turn nine and slid out.

He was unhurt but had his head in his hands.

"I entered the corner a bit slower but I touched the back on the apex of the corner and I lost the front," said the 27-year-old.

"It's something that can happen, but all the risk I was taking to fight back with Jorge wasn't over the limit."

Bagnaia dominated Friday's practice and clocked a track record to grab pole for the sprint and the grand prix on Sunday, when 25 points are up for grabs for the winner.

"I think Pecco will risk a lot tomorrow to win," Martin said of the Italian.

"So to beat him in these conditions is really tough.

"He has nothing to lose now. It's all or nothing."

The season finale had been scheduled for Valencia in a fortnight but it was cancelled on Friday after deadly flooding in that part of Spain.

Organisers are rushing to find a replacement venue.

A minute's silence was held in Sepang before the sprint race to remember the more than 200 dead.

"Right now all my prayers are for Valencia and people at home," said Martin. (AFP)