Marc Marquez led Scott Redding by 0.543 seconds in a soaked MotoGP Austrian Grand Prix second practice from the Red Bull Ring.
A delay of around 20 minutes pushed back the start of the FP2 following a heavy downpour just moments before the session was due to get underway.
No one ventured out immediately, though Suzuki's Alex Rins was the first to put in lap, taking to the circuit five minutes in.
Rins did not set a laptime, but Tech3's Johann Zarco did as he completed a run of laps, putting in a benchmark time of 1:39.637s.
The Frenchman improved on this several times, his run culminating with a 1:37.361s, while the rest of the grid began to explore the conditions.
Aprilia's Scott Redding took over from Zarco with a 1:36.856s, and put in a series of successive session-best laps, the fastest of which a 1:34.538s which put him two seconds clear of the field at one point.
His advantage at the top of the timesheets was quickly cut by Marquez, with the Honda rider usurping him with a 1:34.369s with just under 11 minutes remaining.
A 1:33.995s lap would follow for Marquez, and this would remained unchallenged through to the chequered flag, while Redding held onto second spot, albeit over half a second adrift.
Danilo Petrucci completed the top three once again this afternoon and was top Ducati runner on his Pramac GP18, with factory counterparts Jorge Lorenzo and overall fastest man Andrea Dovizioso rounding out the top five.
Bradley Smith ended the session sixth on the lone KTM present this weekend, with Rins, Jack Miller, Cal Crutchlow and Valentino Rossi filling out the rest of the top 10.
Early pacesetter Zarco fell to 15th as the session drew to a close, while Avintia rookie Xavier Simeon impressed in the tricky conditions in 12th ahead of Marc VDS' Franco Morbidelli, who has been given a three-place grid penalty for riding slowly on the racing line in FP1.
Maverick Vinales struggled in the conditions, as he did in wet races last year, aboard his factory M1 in 20th, with Dani Pedrosa bringing up the rear of the field on the sister works Honda in 23rd.
