Pramac Racing's Jorge Martin won Saturday's sprint at the San Marino Grand Prix with a blistering start from the line to lead all the way to the chequered flag, extending his lead in the riders' championship.

With home fans hoping pole sitter and reigning champion Francesco Bagnaia would make the factory Ducati team proud on home turf, Martin gatecrashed the party to win the sprint with a dominant ride.

Martin now leads reigning champion Bagnaia by 26 points heading into Sunday's race.

"Super happy, I think we did a really good job. Even in practice I was struggling, we were trying to find perfection so that was difficult," Martin said.

"Today I expected to be maybe fighting with Pecco (Bagnaia) but I didn't expect to do that start and from that point ... I was pushing a lot trying to be super focused and finally I even had a gap to keep for the last two laps."

Bagnaia took pole position by breaking Martin's lap record earlier in the day to lead an all-Italian front three of riders from Valentino Rossi's academy.

But sprint specialist Martin had the perfect launch at the start to stun the front row as he overtook the Italian trio to take the lead into turn one, with Bagnaia desperately giving chase in second place.

"Absolutely not happy. After the start it was a disaster. Second position after what happened last week is OK," said Bagnaia, who crashed in the Aragon Grand Prix last weekend.

Bagnaia's teammate Enea Bastianini also had a great start as he moved up from eighth to fourth, much to the delight of the crowd supporting the 26-year-old rider born in Rimini, a stone's throw away from the Misano circuit.

An inspired Bastianini was soon breathing down the neck of Franco Morbidelli in third place, with a podium in his sights. But he ran out of time as the Pramac Racing rider held on for third place behind Martin and Bagnaia.

Marc Marquez was fifth for Gresini Racing after a tight battle with fellow Spaniard and rookie Pedro Acosta, who finished sixth. Australia's Jack Miller will start 12th on the KTM.