Quartararo made the most of Marc Marquez’s injury misfortune as he won the first two races of the campaign to seize control of the championship picture.
But after three subsequent underwhelming displays, it is tight at the top of the riders’ standings.
The Misano event is up next on Sunday at 14:00 local time (13:00 BST), with Quartararo in need of a result.
LAST TIME OUT
The season leader was a measly 13th at the Styrian Grand Prix, missing out on the stunning drama at the front of the field in the second straight Red Bull Ring race.
Miguel Oliveira scored his and Red Bull KTM Tech 3’s first MotoGP victory with a double overtake at the final corner.
The Portuguese pipped both pole-sitter Pol Espargaro and Jack Miller, who had been engaged in a tense tussle on the last lap.
Andrea Dovizioso was a disappointing fifth – to Quartararo’s relief – while Maverick Vinales suffered a scary crash that prompted a red flag in Austria.
WHAT TO LOOK OUT FOR IN SAN MARINO
It will be interesting to see how Quartararo and Vinales approach this week, with their recent tactics failing. After each finishing first and second, respectively, in the first two races of the year, neither rider has come close to even a podium since.
Miller looks to be improving week on week at the moment but, after late disappointment in the previous race, is still waiting to add to his sole 2016 triumph.
Or could this be Alex Marquez’s time to shine? He won at Misano in MotoGP’s eSports series earlier this year.
“Hopefully we can have a good race again,” he said. “Misano is a circuit with a lot of variety, the tight opening section and the faster back section.”
TOP FIVE OPTA STATS
Slumping star? Quartararo’s dip in form has seen him fail to reach the podium in the past three MotoGP races, his worst such run since his first six grands prix in the top category.
Dovi delight? Across the Italian GP and San Marino GP, Dovizioso has five podiums in his past six attempts. He won this event in 2018.
Rossi return? Steady so far this season, Rossi has not made the Misano podium in his past two attempts yet has the most top-three finishes (six) at this track of any current rider. Only he and Marc Marquez have three wins at the San Marino GP.
Honda need help? Not aided by Marc Marquez’s absence, neither Honda team have managed a podium through the first five races of the season. This is their worst start to a year since 1982.
Breakthrough year? Having become the first Portuguese rider to win in the top category, Oliveira has more points (43) so far this year than he did in the whole of the previous campaign (33).
1. Fabio Quartararo (Petronas Yamaha) 70 2. Andrea Dovizioso (Ducati) 67 3. Jack Miller (Pramac Racing) 56 4. Brad Binder (Red Bull KTM Factory Racing) 49 5. Maverick Vinales (Monster Energy Yamaha) 48
1. Petronas Yamaha 102 2. Monster Energy Yamaha 93 3. Ducati 92 4. Red Bull KTM Factory Racing 84 5. Suzuki Ecstar 73
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