Andrea Dovizoso led Ducati teammate Jorge Lorenzo by 0.160s in MotoGP FP2 for the San Marino Grand Prix, while home hero Valentino Rossi moved into the combined top 10 after missing it in FP1.
With rain gathering around the Misano circuit, Marc Marquez wasted no time at the start of the session, going out immediately on a fresh soft slick and taking over top spot first with a 1:33.773s.
The Honda rider improved on his second tour to a 1:32.537s, a tenth quicker than the time Dovizioso topped FP1 with, which lifted him out of the provisional Q1 places.
Yamaha's Valentino Rossi joined Marquez in failing to get into the top 10 in FP1, though went out on a hard rear tyre at the start of the session before switching to a soft for his second run.
Despite the softer rubber, the Italian could only manage third with a 1:33.4s, which was not good enough to put him inside the top 10 on combined times.
Ducati wildcard Michele Pirro ran second for much of the session, before being displaced by Tech3's Johann Zarco on the satellite M1, though was still over four tenths off the pace.
Rossi managed to move into the top 10 overall with a 1:33.147s in the closing stages, but a flurry of improvements forced him out again, with Lorenzo taking over top sot with a 1:32.358s.
The Spaniard's time at the head of the pack last only a moment, as teammate Dovizioso went well over a tenth clear with a 1:32.198s, and remained unchallenged as the session drew to a close.
Lorenzo held onto second, while LCR Honda's Cal Crutchlow completed the top three ahead of top Yamaha runner Maverick Vinales and Marquez.
Vinales' stablemate Rossi fired in a 1:32.786s on his final lap to go eighth and secure a place in Q2 should the forecasted rain affect FP3 on Saturday morning.
Pramac's Danilo Petrucci and the Suzuki of Alex Rins sandwiched Marquez and Rossi, while Marc VDS' Franco Morbidelli headed Zarco to complete the top 10.
A fast late crash for Andrea Iannone at Turn 15 left him down in 16th, but remained ninth on the combined times due to his FP1 lap, which keeps Zarco outside of the provisional Q2 places.
A second crash of the day for Jack Miller meant the Pramac rider could not advance on 14th, while Hafizh Syahrin registered his second fall of Friday in 25th.
Avintia replacement rider Christophe Ponnson scraped into the 107 percent threshold in FP2 with a 1:38.154s, 5.9s off the pace in 26th.
