Marquez fastest at rain-hit Mugello
Honda MotoGP Marc Marquez of Spain competes during the first free practice session of the Italian Grand Prix in Mugello racetrack on May 30, 2014 - by Filippo Monteforte
The Spaniard clocked 1min 48.004sec after two sessions with the second disrupted by intermittent light rain which forced most riders to take cover.
Marquez's best lap was just four-tenths of a second off his own Mugello circuit lap record set last year, and put him 0.382 seconds clear of Yamaha's Valentino Rossi.
Marquez started the first session gently on the Tuscan circuit where he fell twice last year.
"I was unsure this morning and I didn't want to force things. But as the session progressed I felt good," said the Catalan, who has won five consecutive races starting from pole position.
Pramac Racing's Andrea Iannone of Italy set the third-fastest time and was the only other rider to lap within half a second of Marquez.
"It wasn't raining enough to go on grooved tyres and too much to try out the smooth," said Rossi, although the Italian star was pleased with a "positive day".
"I'm not very far either and with Jorge Lorenzo (his teammate) we tested two types of settings that have given good results."