MISANO, San Marino - The Czech Republic's Karel Abraham topped the MotoGP time-sheets after the third and final free practice session at the San Marino Grand Prix on Saturday.

The Ducati rider's quickest time from Friday was not improved upon on Saturday due to heavy rain that rendered the Misano circuit almost impracticable. Only a few riders managed to complete 10 laps, the most enterprising being Valentino Rossi, who went round 17 times.

The Italian, who barely took to the track on Friday, was in sixth place after the three practice sessions, ahead of qualifying for Sunday's race.

Spain's Alvaro Bautista was second fastest, while Spanish championship rivals Jorge Lorenzo, of Yamaha, and Dani Pedrosa, of Honda, finished in ninth and 10th place respectively, having both sat out Friday's session on account of the rain.

Simone Corsi (FTR) was the fastest man over the three Moto2 practice sessions, while Romano Fenati (FTR Honda) took the honours in the Moto3 category.

World championship rivals Jorge Lorenzo and Dani Pedrosa opted out of practice for the San Marino Grand Prix after rain dashed hopes of any useful dry runs. Only 13 of the 21 riders went out on the partly dry Misano circuit with nine-time world champion Valentino Rossi managing just one careful lap before he headed back to the Ducati garage.

"On days like this it's almost impossible to get any feedback on the bike," said Honda's Pedrosa, who has won the last two races and trails Yamaha star Lorenzo by just 13 points in the world title race.

"Actually, we saw in both sessions that the weather was changing so quickly that the riders going out with slick tyres had to come back in because it started raining or the other way around: going out with wets and destroying them in just a few laps as it was drying up again.

"The weather forecast looks better for tomorrow and Sunday, so let's hope we can take advantage of tomorrow morning's session to find a good setting and have a good qualifying."

Moto GP:

1. Karel Abraham (CZE/Ducati) 1min 42.030sec, 2. Alvaro Bautista (ESP/Honda) at 0.363sec, 3. Danilo Petrucci (ITA/Ioda-Suter) 1.148, 4. James Ellison (GBR/Aprilia) 1.174, 5. Michele Pirro (ITA/FTR Honda) 1.297, 6. Valentino Rossi (ITA/Ducati) 1.422, 7. Yonny Hernandez (COL/BQR Kawasaki) 2.535, 8. Jonathan Rea (GBR/Honda) 2.969, 9. Jorge Lorenzo (ESP/Yamaha) 3.392, 10. Dani Pedrosa (ESP/Honda) 4.090

Moto 2:

1. Simone Corsi (ITA/FTR) 1min 39.121sec, 2. Mika Kallio (FIN/Kalex) at 0.052sec, 3. Marc Marquez (ESP/Suter) 0.091, 4. Scott Redding (GBR/Kalex) 0.104, 5. Pol Espargaro (ESP/Kalex) 0.166, 6. Johann Zarco (FRA/Motobi) 0.283, 7. Takkaki Nakagami (JPN/Kalex) 0.349, 8. Bradley Smith (GBR/Tech3) 0.355, 9. Dominiqaue Aegerter (SUI/Suter) 0.368, 10. Thomas Luthi (SUI/Suter) 0.398

Moto 3:

1. Romano Fenati (ITA/FTR Honda) 1min 49.965sec, 2. Maverick Vinales (ESP/FTR Honda) at 1.032sec, 3. Jona Folger (GER/Kalex KTM) 1.123, 4. Kevin Calia (ITA/Honda) 2.630, 5. Alberto Moncayo (ESP/FTR/Honda) 3.154, 6. Dany Kent (GBR/KTM) 3.287, 7. Alex Rins (ESP/Suter Honda) 3.467, 8. Sandro Cortese (GER/KTM) 3.501, 9. Jakub Kornfeil (CZE/FTR-Honda) 4.556, 10. Zulfahmi Khairuddin (KTM) 4.656.