BARCELONA, Spain (AP) Mercedes driver Valtteri Bottas set the fastest time so far in Formula One's preseason testing, with Williams rival Felipe Massa close behind on Wednesday.
Bottas had a lap of 1 minute, 19.310 seconds at the Circuit Barcelona-Catalunya, eclipsing his time from a week ago by nearly four tenths of a second. His lap last week, when preseason testing began, was the fastest at the track since layout changes were made a decade ago.
After a chicane was introduced in 2007, the best lap time had been set by Red Bull driver Mark Webber in 2010, with 1:19.995 during qualifying.
''Fastest laps don't matter in testing. What matters is where you are when you get to Melbourne,'' for the first race of the season, Bottas said.
Kimi Raikkonen went off the track at Turn 3 and put his Ferrari into the barrier during the afternoon session. The Finn ended up with the third-fastest lap, just over a second behind Bottas.
Max Verstappen of Red Bull finished just behind Raikkonen and put in a day's high 102 laps despite having to change its Renault engine and later coming to a stop on the track.
''We had some stoppages obviously, but then in the afternoon we almost completed a full race distance, so that was good,'' Verstappen said.
Lewis Hamilton took over for Bottas after the lunch break, with the three-time world champion focusing on long runs to total 79 laps in four hours. He clocked the sixth fastest time behind Lance Stroll as he likewise shared time behind the wheel with Massa.
Stroll, William's 18-year-old rookie, bounced back from a mishap last week that damaged his car.
Equally promising for Williams was the fact that Massa impressed again with a lap just a tenth of a second slower than Bottas.
The Brazilian driver, lured back from retirement after Bottas left Williams to replace retired champion Nico Rosberg at Mercedes, had been fastest on Tuesday, the first of the final four days of testing ahead of the season-opener in Australia on March 26.
It was yet another bad day for McLaren, which has been plagued by troubles with its Honda engine and showed no signs of catching up with the other teams. Fernando Alonso could only manage the 12th fastest time of the 14 drivers, which was almost 4 seconds off Bottas' pace.
''These are days to learn, but at the same time they are proving very tough because we are spending many hours in the garage,'' Alonso said. ''I hope we can solve the problems in time for Australia.''
Cars have been revamped for the 2017 season following new tire and aerodynamic regulations, becoming a lot bigger and faster than in previous years.
Teams will have two more days of testing on Thursday and Friday.