Barcelona, May 9 - Sahara Force India driver Paul di Resta says the team needs to work extensively on the car in the practice sessions of the Formula One Spanish Grand Prix to get it in top shape for Sunday's race.

Force India lost a substantial amount of track time during the mid-season test in Mugello, Italy, last week after hydraulic issues with the car. The rain on the opening day of the test also hampered preparations of most teams.

Di Resta, who recorded his best result of the season by coming sixth in the Bahrain Grand Prix, said there was lot of work to do before the race.

"(After the Mugello test) There is still plenty of work to do in free practice to get on top of the car, but we have already done the basic checks," di Resta said in a release.

"I probably know Barcelona better than any other track on the calendar. We did two tests there in the winter and I had four days in the car so I already feel quite well prepared, but it is the same for everyone. I expect the field to be incredibly close once again."

The Scot's teammate Nico Hulkenberg rated Circuit de Catalunya here as a tough one.

"It is a track I enjoy and where I have been successful in the past. It is high-speed, there are lots of right hand corners and it is quite tough physically, especially on your neck," said the German.

Force India are eighth in the Constructors' Championship with 17 points from four races.