Rain had been forecast for all three days of practice and racing at Argentina’s Termas de Rio Hondo circuit. It struck during the first afternoon, but only intermittently … so that fears that the morning times might prove crucial for MotoGP’s qualifying session were blown away as several riders went faster in the afternoon.

But should the forecasts prove more dependable tomorrow morning, then today’s times might determine the top ten to secure safe passage directly into the “senior” Q2.

This is potentially bad news for Qatar winner Andrea Dovizioso. The factory Ducati was a surprise last-placer in the afternoon, and dropped to 15th overall.

Hondas took the top honours with Marc Marquez setting one best lap after another to end up on top. His Repsol Honda team-mate Dani Pedrosa did not improve, but was fastest in the morning and still third overall; while LCR Honda’s Cal Crutchlow managed to squeeze himself in between them.

Marquez, Argentinian MotoGP 2018

The other two GP18 Ducatis fared no better than Dovi. His team-mate Jorge Lorenzo was 16th on combined times, and satellite Pramac rider Danilo Petrucci 14th.

Ducati’s hero came from an unexpected quarter, as Reale Avintia rider Tito Rabat placed third in the afternoon session and fourth overall – a huge turnaround for the former Moto2 champion, after two dire seasons on a satellite Honda.

Andrea Iannone was fifth, his Ecstar Suzuki team-mate Alex Rins eighth.

The two factory Movistar Yamahas also speeded up to set times in between them; Maverick Vinales up to sixth, and Rossi eighth.

Miller, Argentinian MotoGP 2018

Johann Zarco (Monster Yamaha) was ninth, with Jack Miller (Pramac Ducati) hanging on to a top-ten slot, both by virtue of morning times.

With the seldom-used circuit (also partially resurfaced) still green, times were relatively slow, some 1.5 seconds off the 4.806-km Argentine circuit’s best lap. Times at the top were also quite spread out, with Marquez four tenths clear of Crutchlow, and Pedrosa another half-second slower.

The change in the weather struck during Moto2’s afternoon session, with the day’s top four times remaining from the first outing in the morning.

Alex Marquez (VDS Kalex) was leading in the afternoon, but was fifth overall.

The fastest time came from veteran Mattia Pasini (Italtrans Kalex).

Rossi, Argentinian MotoGP 2018

He was ahead of the pair of Red Bull KTMs, Miguel Oliveira marginally quicker than Brad Binder; with Pecco Bagnaia’s SKY VR46 Kalex sandwiched between them.

With Isaac Vinales (Kalex) seventh, Danny Kent (Speed Up), Jorge Navarro, Xavier Vierge3 (both Kalex) and Remy Gardner (Tech 3) completed a close top ten, with first to 16th within one second.

Earlier, in dry but windy conditions Moto3 times were also close – from second to 23rd within one second, but slow on the slippery track; and Hondas held the high ground, with five out of the top six times.

Enea Bastianini (Leopard Honda) took to the top in the closing stages of the afternoon session, reinforcing it with an after-the-flag slier that lifted him four tenths clear of team-mate Lorenzo Dalla Porta. A third Italian Honda rider, Tony Arbolino was third, ahead of Livio Loi on the top KTM.

Morning leader and Qatar winner Jorge Martin and fellow Honda rider Kaito Toba held the next two positions, ahead of Argentine rider Gabriel Roderigo (KTM).

Bastianini’s time of 1’50.397 was almost two seconds off the circuit’s best lap.

Aron Canet (Honda), second in Qatar, was 14th after a crash in the morning.