Kimi Raikkonen claimed a narrow edge over his rivals after setting the fastest time in the second practice session of the day in Sakhir, but Red Bull and Ferrari remain in touch as day one ended at the Bahrain Grand Prix.
The Finn moved to the front of the field in the latter half of the 90-minute session and, freed from the need to work on race set-ups, posted a 1min 34.154secs effort to slip in front of RBR's Mark Webber by the scant margin of three-hundredths of a second. The Australian's team-mate, Sebastian Vettel completed the top three, a further tenth back as last year's leading teams showed that they could be the ones to reckon with in 2013, particularly as Raikkonen made a couple of errors on his best lap that could have extended his advantage over the rest.
Twelve months ago, Raikkonen and Lotus team-mate Romain Grosjean chased Vettel home, and the Frenchman backed his colleague up in eighth place, trailing Raikkonen by half a second as he attempted to recover from the KERS problems that hampered his opening session. Lotus again looked strong during the longer runs, with Raikkonen in particular able to post consistent times as he ran one set of medium Pirellis into the ground.
Between them lay both Ferraris, with Fernando Alonso fourth and Felipe Massa fifth on the combined timesheets having set the pace in FP1, the Force India of Paul di Resta and Mercedes' Nico Rosberg. Massa didn't lap quite as quickly as he had managed in the morning session, and trailed di Resta second time around as the Scot again impressed in the best of the recognised midfield entries.
Rosberg continued to have the upper hand over Mercedes team-mate Lewis Hamilton, as the Briton rounded out the top ten, three-tenths back. If 2012 is anything to go by, the Three Pointed Star could struggle with the higher temperatures this weekend, where the upper limit could begin to push F1 records for the hottest race. Ferrari and Force India both looked as though they could push just as hard on race runs, although it was Webber who set the best time on the 'hard' compound tyre.
With Grosjean and Adrian Sutil filling eighth and ninth overall, there was no room in the top ten for McLaren, which had to make do with eleventh and 13th on the day, with Jenson Button and Sergio Perez respectively. Again there was nothing particular bothering either driver, and no offs either, but Button ended the day 0.9secs off the pace on combined times, with Perez a further half-second down.
Behind Force India, Toro Rosso had the most to smile about in the midfield as it established both cars ahead of Williams and Sauber. While Valtteri Bottas' FP1 effort of 1min 35.783secs kept him in 15th overall, both Jean-Eric Vergne and Daniel Ricciardo eased ahead of the Finn, sandwiching Perez in 13th.
Nico Hulkenberg moved ahead of the second Williams of Pastor Maldonado, but still rose only to 16th, but at least he didn't suffer the misfortune of rookie team-mate who, five days on from ramming the back of Sutil in Shanghai, collided with Caterham's Charles Pic, sustaining a left-front puncture in the process. Although the Frenchman could have given his rival more room, it remained an unnecessary incident for this point in the weekend.
Pic finished the session one position, and four-tenths, behind his assailant, topping the 'division three' runners in the process. With usual pacesetter Jules Bianchi hampered by missing FP1 in favour of moneyed former GP2 also-ran Rodolfo Gonzalez, Max Chilton also moved ahead of his Marussia team-mate, while Giedo van der Garde got the better of Caterham 'troubleshooter' Heikki Kovalainen to claim 22nd spot on the combined timesheets.