The Spanish Ducati rider, bidding for a record-equalling eighth world title, started on pole and recovered from a crash to finish ahead of teammate Francesco Bagnaia and Franco Morbidelli for his 17th sprint victory.

Overall leader Marco Bezzecchi started poorly and later crashed out, failing to score any points, with Jorge Martin and Pedro Acosta, second and third overall, also not adding to their tallies.

"The truth is that we had a lot of luck," admitted Marc Marquez, who was able to take advantage of his crash to switch to a wet bike.

The race started under grey clouds and rain began to fall three laps in, after Martin had already pulled out because of a technical problem with his Aprilia.

Marc's brother Alex, who won the Spanish MotoGP last year, had impressed on the dry on Friday and carried his good form in Jerez into the race by taking the lead on the seventh lap.

The rain increased in intensity and riders began to fall, with Toprak Razgatlioglu and Lorenzo Savadori colliding.

Marc Marquez was next to tumble, but had the presence of mind to cut across the grass back to the pit lane and change bikes, while the other race leaders ploughed on. However, they too soon had to change bikes under the downpour.

"We were lucky to crash on the last corner so that the bike didn't stall, that's when I could breathe, I waited for everyone to go past because the whole group was coming, and then I was able to go into the pits, change the bike," explained Marc Marquez.

Alex Marquez came to grief shortly after his older brother's mishap and it was two-time world champion Bagnaia who took the lead.

However, Marc Marquez overtook him with three laps remaining and went on to triumph.

Victory took him up to fourth overall, 24 points off leader Bezzecchi ahead of Sunday's main event.