Lotus boss Eric Boullier still surprised by Grosjean's progress

Despite being in only his first full season of F1, Grosjean has produced some impressive qualifying performances as well as two podiums up until now.

And although the decision to sign Grosjean as Kimi Raikkonen's team-mate was Boullier's, he has confessed that he never expected him to be able to deliver the kind of drives he is putting is now.

"He keeps surprising me, because he has the same characteristics as we always knew he had," Boullier told AUTOSPORT. "He is a hard worker; he listens, and he works a lot with his engineers.

"But it is not only work, because he learns from the data, from advice, from everything. What is I think is very promising is that he has the pace and as he has shown in Canada he can do a full race.

"He did 45 laps on these tyres, with being very consistent in not destroying them. He is learning and learning fast."

Grosjean is now just two points behind team-mate Kimi Raikkonen in the drivers' standings, and Boullier says that extra work needs to be done in also helping the Finn improve his qualifying performances.

"We definitely need to help Kimi, as they have different driving styles," he said. "We had this issue in Canada with the differential which doesn't help, but we need to work on helping him qualify better. For the race there is no issue."

With Lewis Hamilton becoming F1's seventh winner from seven races in Canada, Lotus now has the best chance to produce an eighth different victor in the next event in Valencia.

When asked about that possibility, Boullier said: "It's a nice pressure. If it is hot it should be okay. Then the layout of Silverstone and Germany should also help us, and Hungary maybe."