By Alan Baldwin
SPIELBERG, Austria (Reuters) - Lewis Hamilton seized pole position for the Austrian Grand Prix on Saturday in a damp qualifying session that saw both the Formula One world champion and his Mercedes team mate Nico Rosberg skid off on their final laps.
The pole was Hamilton's seventh in eight races -- the same number he managed in all of last season -- and 45th of his career, taking him to third equal with Sebastian Vettel on the all-time list behind Michael Schumacher and Ayrton Senna.
It also completed a year of domination by Mercedes, with Brazilian Felipe Massa's pole for Williams in Austria last June the last time any driver from outside the team has started from the top slot.
"It was quite a difficult qualifying session for everyone because of the track conditions," said Hamilton, who spun off at turn one as he started his final quick lap on a drying track after morning rain.
"I was pushing that bit extra on the next run and just locked the rears," he added.
Rosberg, who was two tenths slower than Hamilton going into his final lap, pushed just a bit too hard and careered across the runoff and into the gravel just as it seemed he was going to be quicker.
"I went on the astroturf out of the second to last corner. Maybe that was still a bit wet or something or I just overdid it after that, I'm not sure. I just lost it there into the last corner," said the German.
"I knew I had to go for it."
Ferrari's Vettel will line up in third place with Massa fourth for Williams and 2015 Le Mans 24 Hours winner Nico Hulkenberg fifth for Force India.
Mercedes-powered cars filled five of the top six slots at a 'power' circuit.
"Generally the Mercedes-powered cars can turn up the performance a bit. Even the Williams were also a lot closer than they were in practice," said four-times champion Vettel.
At a scenic circuit owned by energy drink giant Red Bull, 17-year-old Dutch rookie Max Verstappen provided some cheer for the unhappy hosts with seventh place on the grid for Red Bull's sister team Toro Rosso.
Both Red Bull's main drivers Daniel Ricciardo and Daniil Kvyat have 10 place grid penalties as a result of engine replacements.
Ferrari's Kimi Raikkonen failed to get through the first phase of qualifying and was 18th before penalties are applied to others ahead of the Finn.
"How is that possible?," exclaimed the Finn, with the expletive deleted.
An element of farce was added to the session with McLaren's Fernando Alonso and Jenson Button each facing 25 place grid penalties in a field of just 20 cars for exceeding their allocation of power unit components.
Alonso qualified 15th while Button was 17th, meaning they will have to serve time penalties on Sunday as well as starting from the back with new Honda president Takahiro Hachigo attending the race to see for himself how the McLaren partnership is faring.
(Reporting by Alan Baldwin, editing by Toby Davis)