Jarno Trulli fears his Toyota team will not be as competitive at the Spanish Grand Prix as it was in the previous races.
The Japanese squad, enjoying its strongest season to date, started from pole position in Bahrain, but Trulli was only capable of securing seventh position in today's qualifying at Barcelona. Teammate Timo Glock will start from sixth.
Trulli believes the time spent on working on the new developments introduced for this race has cost Toyota, and the Italian reckons the team is not as strong as in the first four outings.
"I have been spending most of the weekend trying new things, all the new bits we brought here for the car upgrade. You have to spend time to know what's right and what's wrong," Trulli told reporters after qualifying. "This cost us a little bit of time in terms of set-up and we have seen straight away that we are not so competitive. It was a tough job to get through Q1 and Q2. I also had a bit of traffic.
"But once I was in 3 I felt much better because, as usual, I'd been working on race trim. So the car was more settled and balanced. Seventh position is a pretty good position."
He added: "We are struggling with stability and the rear end of the car, so we need to find some more speed and more balance. This comes more on the aero than anything else. We could have spent a bit more on the set-up work, but unfortunately we had so many new bits on the car that we needed to confirm. But time is limited on the car."
Trulli said the main problem was the car's handling in slow corners.
"We are struggling at the moment," he added. "Here we are not so good, if you look at sector three we are missing some downforce.
"Our car is more competitive in medium to high speed. We have some work to do. It's still a car, but if we want to match the race winner we need to take the step.
"Tomorrow will be an interesting race because we will see very different strategies, possibly. I can tell you my lap time was really good in Q3."