Following Sunday's season-ending Valencia Grand Prix, a two-day post season MotoGP test began at the circuit on Tuesday.
Day one was marred by poor weather, which caused seven of the 21 riders to remain in the pits and prompted the Factory Yamaha team to send Valentino Rossi and Jorge Lorenzo to Aragon for day two.
Unfortunately, it rained at both Valencia and Aragon on Wednesday morning - but conditions at Valencia have finally improved enough for some mid-afternoon slick-tyre runs.
That convinced 2012 title runner-up Dani Pedrosa to head out for the first time since winning Sunday's race - and Pedrosa was on top of the timesheets by 3:30pm, when new Repsol Honda team-mate Marc Marquez finally made his MotoGP debut.
UPDATE: Moto2 champion Marquez got to within 2.1s of Pedrosa's best lap time (now down to a 1m 33.7s) at the end of his first seven-lap run on the RC213V.
Fellow MotoGP rookie Bradley Smith had made his own debut, on wet tyres, shortly after midday. Smith is yet to ride with slicks.
As well as Pedrosa, Marquez and Smith, Cal Crutchlow, Shane Byrne, Danilo Petrucci and Lorenzo sat out day one of testing. Ben Spies, moving from Yamaha to Ducati for 2013, is not present due to recent surgery. His place is being taken by new Ducati test rider Michele Pirro.
Alvaro Bautista's Tuesday time was set on slicks, just before rain arrived.
Despite the poor weather at Aragon, Rossi - who rode 28 wet laps during his Yamaha return at Valencia on Tuesday - and reigning champion Lorenzo have both reportedly been on track, where some World Superbike teams are also testing.
Lorenzo fell without harm on the wet track.
for extensive picture coverage from the Valencia MotoGP test...
1. Dani Pedrosa
ESP Repsol Honda (RC213V) 1m 34.911s
2. Nicky Hayden
USA Ducati Team (GP12) 1m 35.484s
3. Michele Pirro
ITA Pramac Racing (GP12) 1m 35.544s
4. Andrea Dovizioso
ITA Ducati Team (GP12) 1m 35.885s
5. Randy De Puniet
FRA Aspar (ART CRT) 1m 36.132s
6. Danilo Petrucci
ITA Came IodaRacing (Suter-BMW CRT) 1m 36.157s
7. Alvaro Bautista
ESP Honda Gresini (RC213V) 1m 36.418s
8. Andrea Iannone
ITA Pramac Racing (GP12) 1m 38.251s
9. Aleix Espargaro
ESP Aspar (ART CRT) 1m 43.517s
10. Marc Marquez
ESP Repsol Honda (RC213V) 1m 44.934s
11. Bradley Smith
GBR Yamaha Tech 3 (YZR-M1) 1m 46.566s
12. Hector Barbera
ESP Avintia (FTR-Kawasaki CRT) 1m 47.386s
USA Forward (FTR-Kawasaki CRT) No Time
GER LCR Honda MotoGP (RC213V) No Time
JPN Avintia (FTR-Kawasaki CRT) No Time
CZE Cardion AB (ART CRT) No Time
GBR Yamaha Tech 3 (YZR-M1) No Time
GBR Paul Bird Motorsport (ART CRT) No Time
ITA Forward (FTR-Kawasaki CRT) No Time
ESP Yamaha Factory (YZR-M1) Not present
ITA Yamaha Factory (YZR-M1) Not present
Fastest Day 1 time:
ESP Honda 1m 35.936s
Official Valencia MotoGP records:
ESP Honda 1m 30.844s
Fastest race lap:
AUS Ducati 1m 32.582s