BARCELONA, Spain (Reuters) - Sunday's Spanish Grand Prix could be a turning point for Formula One champions Mercedes in their battle to tame a bouncing car.
Seven times world champion Lewis Hamilton and team mate George Russell said on Friday they expected the Circuit de Catalunya to determine the direction the team followed on development.
The early signs were promising as the team tested performance upgrades, with Russell second fastest and Hamilton third in practice.
"I'm positive, yeah. Super happy with the progress, so a big, big, big, big thank you to everyone back at the factory for not giving up and for continuing to push," Hamilton told reporters.
"We're not the quickest yet, but I think we're on our way. It's the first time we've driven down the straight without bouncing. We still have some bouncing, but it's way better."
Team boss Toto Wolff said this month that he expected an answer after Barcelona to whether Mercedes had got their design philosophy right or wrong after eight years of domination.
Hamilton added: "We will understand from this weekend whether where we are is the right direction and, if not, we'll ... move in another direction.
"I think it won't mean that we have to start from scratch, it will just probably be a side step in another direction," said the Briton.
Russell, who arrived from Williams at the end of last season to replace Valtteri Bottas, said it had taken time to identify the problem and come up with possible solutions.
"Miami was a first taste of the direction we need to take and this weekend will be the second taste," he said.
"I think we'll have a good conclusion after this weekend, if we can continue down the path that we've chosen, or we need to go down a different path.
"If this is the path, we're not going to suddenly see us on the top step of the podium," he added. "Either way, we will have a positive outcome from this weekend."
(Reporting by Alan Baldwin, editing by Ken Ferris)