Ferrari and Lotus insist they cannot be confident about their Bahrain Grand Prix race prospects despite emerging as early favorites by the end of Friday practice.
Lotus driver Kimi Raikkonen set the outright pace as he led practice two, while Felipe Massa had been fastest for Ferrari in the morning. In addition to these headline times, both teams also showed strong form on longer runs later in the sessions, and appeared to have an edge in tire management.
Raikkonen insisted that he was unhappy with his Lotus, though.
"It didn't feel particularly good today," he said. "I think there are improvements to be done but the lap time was pretty OK. I made a mistake in the last corner so we lost a little bit of time, but I feel we can improve a bit for tomorrow."
Despite the indications from practice, Massa believes Ferrari also has issues to address with tire wear.
"The car behaved well but there is big, big degradation on the rear tires," he said. "That is something where we need to understand what to do for the race.
"It is not just for us, it is for many teams. For sure if you see a team that has better degradation with the tires, this car can be very strong in the race."
Ferrari's deputy chief designer Simone Resta, project leader on the 2013 car, also refused to accept that his team had a good chance of maintaining the winning form it showed in China last weekend.
"Let's leave the surprises for Sunday," he said. "It's a little bit early to draw conclusions. The race is on Sunday and we need to see better with more data.
"I think we are showing reasonably good race pace and we need to close the gap in qualifying to the fastest times."