Tonio Liuzzi has denied that the loss of former technical chief James Key to Sauber earlier this year has led to Force India's form tailing off as the season progressed.
Force India made the strongest start to a Formula 1 season in its short history and was a regular top 10 fixture in the first half of the championship. But it has found it harder to break into Q3 in recent weeks, and what had been a comfortable sixth place in the constructors' standings is now under threat from the fast-closing Williams team.
Key left Force India in February and was announced as Sauber's new technical boss shortly afterwards. He had been credited with a major role in Force India's progress, but Liuzzi insisted that the team's decline in form through the season was a natural consequence of its underdog status, not a reflection of Key's absence.
"James Key was a great person who worked really well in the team, but we were fighting at the beginning of the season with big teams," Liuzzi said. "Sometimes from the outside it was difficult to realise, but we were fighting with Mercedes, with Renault, with teams that have won championships.
"We are a small team, and in all the years we've seen that development is tougher for the small teams with the smaller budgets.
"We are trying really, really hard and I think we are still doing a great job, but Williams is not the last team in the field. They started on a little bit of a down side and they made a huge step forward, Renault as well. I think it's a bit of a normal progress in the season.
"But we are still doing great - we are still there in sixth in the championship and we will still fight to the end, but we have to expect something like that [drop off]."
Last season Force India surged into contention in the latter part of the season, and though Liuzzi acknowledged that its development programme had been an element in this, he said it was more due to particular circuits suiting the 2009 car.
"Last year the team did a big development for Valencia and after that the style of tracks was really well-suited to our car and it showed with the results, but then it was quite clear because we went from Monza where we were maybe the second-fastest car in the field, to Singapore where we were 15th and 16th," he said.
"So we knew what our strength was, and this year we realised that other teams understood it and they made our life difficult - because this year at Spa and Monza we were not as competitive. But we were more competitive everywhere else, we have a car that from the beginning to the middle of the season was in Q3 and the top 10 and we were always fighting for that area.
"For sure we have a much more competitive car overall, but we lost a bit of our top strength on high-speed circuits."
Liuzzi cited issues with tyre temperature in qualifying as the main factor holding Force India back recently. The team has regularly had to make its way through the field to score in races after qualifying in the midfield.
"We discovered a few issues that we have in qualifying," the Italian said. "Starting from Valencia onwards we've had a problem putting heat into the tyres, and we are working a lot in developments on this.
"We seem to struggle more in qualifying than in the race. We always have a stronger race pace compared to qualifying. That could have been a down side from the middle of the season onwards. But everybody has realised that Williams and Sauber are closer.
"We are still there. We are not nowhere, we are fighting with them, it's just much tougher getting into Q3 or the top 10."
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