Ferrari's Sebastian Vettel was fastest in a wet final free practice for the Austrian Grand Prix with Mercedes very much in the hunt, while McLaren's woes got worse.
Vettel lapped the Red Bull Ring in a best time of 1:09.994 seconds on a dry track and soft tyres before the rain began to fall halfway through the session and made the rest meaningless.
Reigning F1 world champion Lewis Hamilton was second fastest for Mercedes, 0.017 slower, with Ferrari's Kimi Raikkonen third on the time sheets.
Nico Rosberg, Hamilton's team mate and last year's winner in Austria when the race made its return to the calendar after an 11 year absence, was fifth.
The main talking point during the session, apart from the appearance of a hare on the track and the slippery conditions, was the totting up of engine penalties that left McLaren drivers Jenson Button and Fernando Alonso in a race to be last.
Alonso was handed a 20-place grid penalty on Friday, for a change of his car's Honda engine that exceeded his season's allocation, and Button trumped that on Saturday with a 25-place drop.
The Spaniard, whose car stopped on the pit straight and brought out the red flags, is likely to match Button's penalty due to an expected gearbox change that would bring an additional five place drop -- on a grid with only 20 cars.
The grid drops, embarrassing for the team with Honda president Takahiro Hachigo due to attend the race, will have to be taken in the form of additional time penalties.
[highlight ]Austrian Grand Prix, Free Practice 3 - Saturday, 20 June 2015[/highlight]
| Pos. | No. | Driver | Team | Time | Gap | Laps |
| 1 | 5 | Sebastian Vettel | Ferrari | 1:09.994 | | 16 |
| 2 | 44 | Lewis Hamilton | Mercedes | 1:10.011 | +0.017s | 16 |
| 3 | 7 | Kimi Räikkönen | Ferrari | 1:10.177 | +0.183s | 12 |
| 4 | 11 | Sergio Perez | Force India | 1:10.221 | +0.227s | 14 |
| 5 | 6 | Nico Rosberg | Mercedes | 1:10.332 | +0.338s | 23 |
| 6 | 19 | Felipe Massa | Williams | 1:10.408 | +0.414s | 18 |
| 7 | 77 | Valtteri Bottas | Williams | 1:10.417 | +0.423s | 14 |
| 8 | 33 | Max Verstappen | Toro Rosso | 1:10.436 | +0.442s | 23 |
| 9 | 13 | Pastor Maldonado | Lotus | 1:10.576 | +0.582s | 12 |
| 10 | 8 | Romain Grosjean | Lotus | 1:10.863 | +0.869s | 8 |
| 11 | 27 | Nico Hulkenberg | Force India | 1:11.009 | +1.015s | 14 |
| 12 | 9 | Marcus Ericsson | Sauber | 1:11.058 | +1.064s | 22 |
| 13 | 55 | Carlos Sainz | Toro Rosso | 1:11.139 | +1.145s | 18 |
| 14 | 26 | Daniil Kvyat | Red Bull | 1:11.139 | +1.145s | 14 |
| 15 | 14 | Fernando Alonso | McLaren | 1:11.168 | +1.174s | 13 |
| 16 | 3 | Daniel Ricciardo | Red Bull | 1:11.819 | +1.825s | 10 |
| 17 | 12 | Felipe Nasr | Sauber | 1:11.906 | +1.912s | 9 |
| 18 | 22 | Jenson Button | McLaren | 1:12.616 | +2.622s | 16 |
| 19 | 28 | Will Stevens | Marussia | 1:13.328 | +3.334s | 14 |
| 20 | 98 | Roberto Merhi | Marussia | 1:13.960 | +3.966s | 8 |