Paul di Resta is confident Force India can catch up with Sauber and Williams in the midfield after a slightly disappointing start to the season.

14935 - The best is yet to come - di Resta

Force India finished sixth in the constructors' championship last year but is currently lagging behind Sauber and Williams, which have both scored impressive results. Force India's highest finish was di Resta's sixth place at the Bahrain Grand Prix, but the Scot is confident there is more to come from his team.

"I think me and Nico have a good relationship, we're obviously pushing each other along but also trying to develop the car because we feel that we're a little bit behind the likes of Sauber and Williams at the moment," he said. "And to overcome that we need to be doing a good job in the race. Over the weekend you've got to maximise what you have, and that's what we're going to try to achieve again this weekend.

"We need to understand the car a bit more in terms of what we're bringing in terms of upgrades. That's what we're trying to achieve. But I have every confidence the team will achieve that because last year our development rate went very high from mid-season, so we're certainly hoping we can do that this year. I don't believe we're getting the maximum out of the car yet but we'll try to achieve that this weekend again. It's a different philosophy, obviously, being a bit lower downforce here. So hopefully that will suit us slightly better."

Di Resta said Force India has yet to see the full performance from the latest major update added to the car at the Spanish Grand Prix two races ago.

"It wasn't a secret that we struggled at the beginning of the year, to what we initially first thought," he said. "Since then we've rapidly moved on. If we can do that… I think we brought a good upgrade to Barcelona. We obviously developed that forward over that weekend. Monaco was difficult to understand how much so I think here will probably be a truer reflection on what we can expect for the up and coming races."