Lotus driver Romain Grosjean ready to blossom in 2015 season

Comparing this year’s Mercedes-powered Lotus Formula One car to the team’s troublesome 2014 one is child’s play for Romain Grosjean.

“I was playing with my son and he has got a rugby ball and a basketball,” the French driver said yesterday when explaining the different characteristics of the cars.

“I was trying to bounce the rugby ball and it was going all over the place, and the basketball was going straight.”

There were no prizes for guessing which car was the basketball.

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“This year at least, when you get into the corners the car feels stable. You don’t have any bad surprises, it’s predictable and you can push harder,” Grosjean said. “I had a big smile on my face as the car was nice to drive.”

Lotus finished fourth overall in 2013, winning in Australia with Finland’s Kimi Raikkonen before he departed for Ferrari, but slumped to eighth with 10 points in 2014, when a new V6 turbo hybrid power unit replaced the old V8s.

The team also had financial problems, with some key staff leaving along with sponsors, but they are confident they are back on the right track after switching from Renault power to Mercedes.

Whether that can put Grosjean and Venezuelan teammate Pastor Maldonado back on the podium remains to be seen, with the Mercedes works team again expected to set the pace after enjoying a dominant 2014, but the Frenchman was hopeful.

Speaking after the announcement of an extended partnership between Lotus F1 and Denmark-based sponsor Saxo Bank, Grosjean said that the team was moving in the right direction.

“It felt pretty good, to be fair,” he said of his first experience at the wheel of the new E23 car in testing in southern Spain last week.

Lotus completed 190 laps during the four days in Jerez, compared to a total of 111 in 2014 preseason testing.

“We know Mercedes is the best power unit on the grid ... our start with them has been very smooth.

“Everything is working as we would like, so at least that is a question mark removed from the equation.

“Last year at this stage was difficult for us. We missed Jerez and then went to Bahrain and didn’t do a lap, so it’s been a big difference.”

Maldonado, a winner with Williams in 2012, said recently that Lotus — champions in their former guise of Benetton and Renault — had all the tools to be competitive and win again, but Grosjean refused to be drawn into too much optimism.

“I think it’s too early to say,” said the 28 year old, who is still waiting for his breakthrough first win in Formula One after five third places and a second in 2013.

“Realistically, we want to be very often in the top 10 and would like to be top five.

“Why not be back on the podium? I still think there are teams which are a bit stronger than we are ... but of course we are going to do everything we can.

“We do have stability from 2014 to 2015 that we didn’t have the previous year, so that’s a very good way to start the season. Everyone knows his job and everyone is doing it properly, and that’s going to certainly help us.”

Now the only French driver on the starting grid, with Jules Bianchi seriously injured in a crash in Japan last year and Jean-Eric Vergne losing his seat at Toro Rosso, Grosjean hoped to fly the flag.

“I am the only one left. There were four [French] in 2014, three in 2013,” he said.

“Jules is always with us in thought, but being the only French driver on the grid, it’s nice to feel that there is a lot of support behind you.”