Hamilton, who has a 10-point advantage over German team mate Nico
Rosberg after winning the last three races, produced the fastest lap
yet of the new Sochi circuit with a best time of one minute 38.726
The 2008 champion spun late in the session at the penultimate
corner, but escaped without damage.
"It was a tremendous lap, he seems to extract the maximum out of the
car at the moment," Mercedes motorsport head Toto Wolff said.
"Somehow, Lewis seem to nail it on first lap, Nico seems to struggle
a bit more, but this is just practice," the German told the BBC.
Rosberg was second fastest, 0.290 slower, on a warm and bright
morning at the 5.8km track that snakes around the Black Sea resort's
imposing Olympic Park venues used for this year's Winter Games.
Hamilton, chasing his ninth win of the season on Sunday, was also
fastest on Friday, although Rosberg was quicker in the morning.
Finland's Valtteri Bottas was third for Williams in a session that
was briefly halted after the McLaren of Danish rookie Kevin
Magnussen stopped on track with a gearbox problem that will bring a
five-place grid penalty.
Red Bull's Australian Daniel Ricciardo, the only driver other than
the Mercedes duo to win this season, was fourth fastest.
[to top of second column]
Venezuelan Pastor Maldonado failed to set a lap time with mechanics
working on his Lotus.
Sunday's race comes after a dark weekend in Japan, with Marussia's
Jules Bianchi critically injured in hospital after the Frenchman
crashed into a recovery tractor. Britain's Max Chilton is the team's
sole driver in Sochi.
(Editing by John O'Brien)
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