Belgian F1 GP: Mercedes' Lewis Hamilton extends pole streak at Spa

Rosberg was narrowly faster than team-mate Hamilton in Q2 at Spa, but the reigning world champion reversed the situation by a massive 0.446 seconds after their respective first runs in Q3, then lowered his benchmark time to a 1m47.197s on his second run to secure pole.

In doing so Hamilton became the first driver to score six pole positions in a row in a single season since Mika Hakkinen in 1999 and also clinched the FIA pole trophy for 2015.

Rosberg also improved on his second run, but he dropped almost half a second to his title rival in sector two of the circuit, which runs from Les Combes through the double left-hander at Pouhon to the right-hander at Stavelot, so wound up second best again.

Ferrari would normally be expected to fill row two of the grid, but Sebastian Vettel could only lap ninth fastest in his SF15-T, while team-mate Kimi Raikkonen failed to make it into Q3 at all after his car broke down on track with what the team believes was a loss of oil pressure.

Mercedes-powered Williams, Lotus and Force India thus filled the next three places on the timesheet, as Valtteri Bottas, Romain Grosjean and Sergio Perez all lapped to the same tenth of a second, but well over a second adrift of Hamilton.

The Renault powered Red Bull of Daniel Ricciardo rounded out the top six, ahead of the second Williams of Felipe Massa and the second Lotus of Pastor Maldonado.

Carlos Sainz Jr's Toro Rosso rounded out the top 10, albeit well adrift of the rest of the Q3 runners.

Perez had set a stunning fourth-best time in Q2, but Nico Hulkenberg failed to make the top 10, finishing up over three tenths adrift of his Force India team-mate in 11th.

Red Bull's Daniel Kvyat was another surprise failure in Q2, finishing up 12th, ahead of Marcus Ericsson's Sauber.

Raikkonen ended up 14th, ahead of the Toro Rosso of Max Verstappen, who took no part in Q2 after suffering a suspected loss of power with his Renault engine in Q1.

Sauber's Felipe Nasr was the big loser among the tight midfield battle in Q1.

Verstappen's Toro Rosso was vulnerable thanks to a suspected loss of power early on in his final flying lap, but Nasr fell short of beating the Dutch teenager by 0.121s, so wound up 16th.

Jenson Button was a second further back in the best of the two McLaren-Hondas.

The 2009 world champion described his 1m50.978s effort as "the best lap I've done for a long time", but it was only good enough for 17th place.

Team-mate Fernando Alonso was nearly half a second adrift in the other MP4-30, after sitting out the final practice session with an exhaust leak.

Will Stevens won the private battle of the Manor/Marussias at the bottom of the timesheet, beating team-mate Roberto Merhi by 0.151s.

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