Greater Noida, Oct 21 (IANS): Force India team principal Vijay Mallya says they must improve to stop Sauber overtaking them for sixth place in the Formula 1 Constructors' Standings.

Force India, who were fifth ahead of McLaren until the mid-season break, have only managed three points in the second half of the year. As a result of their dipping form, McLaren have got past them and are 21 points clear of the Silverstone squad with 81 points.

With no further development work expected on the car in the remaining four rounds, Force India will have to pull something special out of the bag to keep the fast improving Sauber at bay. The Swiss team has amassed 38 of their 45 points in the last four races and seem to have the fastest car in the mid-field battle.

Mallya admitted they need to take a step forward.

"Sauber have been doing a very good job lately. They are the in-form team at the moment and they have been taking all the opportunities that were presented to them. It's going to be a real fight in these last four races: we need to make a step forward to hold them off, because they can qualify well and they have strong race pace as well," said Mallya in a team preview ahead of the Indian Grand Prix here this weekend.

"The races after the summer break haven't been very positive in terms of scoring points, but the morale in the team remains strong. Korea and Japan were not the easiest of weekends, but everyone in the team is working really hard to recapture our early form. It's all a matter of finding the right balance with the car - when we do that, we will be back in the points," he said.

Mallya's team will be the sole Indian representation on the grid with the absence of a local driver.

On the home race, Mallya said: "Our home race is always a very proud weekend for everyone in the team: the atmosphere at the track is incredible and we always enjoy plenty of support. The track itself is one of the best in the world. It's also a good one for us - in the last two years we scored points in both races, so a similar result would be a good target for the team."