Romain Grosjean will begin his day of testing today in Barcelona at the wheel of a new Haas chassis in a bid to find solutions to handling problems which have hindered his and the team's progress in the last few races.
Following an impressive debut for the rookie US squad in Australia and Bahrain, Grosjean has struggled with issues affecting the balance of his VF-16 chassis.
It is hoped that the new chassis will solve the car's outstanding problems which, although identified by Haas, could not be remedied on Grosjean's original car.
"We've been struggling since China with something we don't quite yet understand so we're going to change everything for the test," said Grosjean.
"It's been hard for everyone because in terms of work everyone has been doing a great job of looking at the data and finding a solution - making the car on paper better - and we always underline that these are problems that Esteban doesn't have.
"It's quite strange that it's only happening in one car and that's why it's going to be very important for us at testing to change the chassis and put the set up in and see if things get better."
In the face of the Frenchman's disappointing performance of late, and at the start of last week's Spanish GP weekend, changes were made to his car in Barcelona on Friday evening, but failed to produce any improvement.
"We changed the philosophy of the set-up we'd made for China so this should bring the car back to where it was but actually it didn't happen as much as we wanted.
"We went in a good direction that's why I'm saying that everyone has been working well. But under the table there's something that we don't see or understand.
"That's why we want to change the chassis to see if there's something weird in terms of torsion or something that's creating issues."
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