SPA-FRANCORCHAMPS, Belgium -- Sebastian Vettel said Ferrari has to improve overnight, declaring himself "not entirely happy" with the car after opening practice in Belgium.
Vettel finished fourth in FP2, four tenths behind Force India's Nico Hulkenberg and a full second behind Max Verstappen, who led a Red Bull one-two out in front. Despite a number of driver complaints about tyres Vettel refused to use that as an excuse for Ferrari's pace.
"Today was a tricky day, very slippery," Vettel said. "It's very hot. I don't think it matters what tyres you have, it's slippery for everyone. We'll see, we have to improve our car. It's not where we want to be."
The FP2 result must be judged with the knowledge Mercedes did not venture on to the super-soft tyre - this weekend's fastest compound - in FP2. The team also focused Lewis Hamilton primarily on long runs, aimed at perfecting his race set-up, in the knowledge he is set for a big grid penalty on Sunday following an engine change.
When asked if that penalty increased Ferrari's chances of a first win of 2016, Vettel replied: "I don't know how far he is starting back from ... It's quite warm for Spa. I think everyone was struggling to make the tyres last, I was sliding a lot.
"At least the cars I saw were struggling a lot, which is a bit of a shame but it's the same for everyone. We will try and work on that. The competitiveness is difficult to say, I don't think everyone had clear runs. it's difficult to judge."