|© Ker Robertson/Getty Images/Red Bull Racing
Renault-powered teams continued to struggle on the opening day of the final pre-season test in Bahrain on Thursday while the Mercedes-runners maintained their tight grip at the front.
Sergio Perez led the timesheets in his Force India with 105 laps ahead of the untroubled Williams of Valtteri Bottas, who did 23 more. Nico Roberg in the Mercedes was 11 shy of a hundred laps, while McLaren's Kevin Magnussen managed 109.
In contrast, the four Renault-powered machines totalled 146 laps between them with defending champions Red Bull accounting for 39 of those at the hands of Daniel Ricciardo, who started the day well with a series of laps but had to abort later after an exhaust problem popped up.
"We still had a few issues today, but at least when the car was on track it was much more useful running and we made progress in the morning," said an upbeat Ricciardo. "It’s getting there."
Without adequate mileage, all the Renault-runners featured in the bottom half of the charts. An exhaust issue shortened Lotus' running after the new specification caused damage to the surrounding area of the car while a technical failure robbed Toro Rosso of track time.
Favourites Mercedes piled on the laps with long runs coupled with setup evaluation with the intention of running as close as possible to the season-opening Melbourne race specification but problems brought running to an end one hour earlier than planned.
"That was not a fantastic day for us," Rosberg reported. "We tried some new parts on the car and you find out a lot through doing that.
"But unfortunately we did not only discover good things today... This shows that we are pushing everything to the limit and we still have a massive challenge in front of us during the last three days of testing."
Ferrari's programme too was aimed at preparation for the first race of the season but work got delayed in the morning because of a problem on the car that took some time to fix.
"We had a small problem today, which limited the number of laps but still managed to learn some new things about the car," said Kimi Raikkonen. "On the final day of the test, we will put everything together that we have learned so far and will concentrate on the conditions we will encounter in the races."