Kimi Raikkonen reckons Ferrari's SF15-T is a "very nice car" and a vast improvement on last year's challenger.
The Finn was in action at the Circuit de Catalunya on Thursday, kicking off the second pre-season test for Ferrari.
Covering 74 laps, Raikkonen finished second quickest having posted a 1:25.167 on the medium Pirelli tyres.
That was just 0.156s down on Pastor Maldonado's pace-setting lap time which he did on the quicker soft tyres.
And although happy with the day's work, Raikkonen concedes lap times in testing don't always tell the full story.
"It's not that different from Jerez, we don’t know about the fuel other cars had, and some of them were on soft tyres. We keep doing our stuff, have made our plan and try to follow it," he said.
"The car is a completely different story from last year's, we've still got a long way ahead of us but the team is working well and has produced a very nice car."