Tonio Liuzzi has admitted that he faces a much tougher challenge on his second appearance for Force India as the Italian gets set to face the Singapore street circuit for the first time this weekend.

Liuzzi made his return to F1 competition last time out after being called up by the Silverstone-based squad to replace Giancarlo Fisichella, after he made the move over to Ferrari for the remainder of the season.

Despite being out of the sport for some time, Liuzzi was on the pace from the outset and qualified in an impressive seventh place - helping Force India to get both of its cars into Q3 for the first time - and ran well in the race before being forced out by a driveshaft issue.

The Italian will now hope to impress again for the team in his second race, although he concedes that - having been out of an F1 race seat since 2007 - he still has work to do to get up to speed and will face a bigger challenge at a circuit he has never raced at before.

"I don't think I'm yet at the pace where I was two years ago, when I was completely confident about the car," he said. "I think there is still a lot to come. It was a big shame for the team that we couldn't score points in Monza, but I feel happy because fortunately I saw that once the car is fast and competitive I can give a good performance and I can fight with the big guys in the World Championship.

"For sure Singapore will be much tougher. We've been working in the simulator to get to know it better, but it will be a much tougher event. We'll have to see how the car is there because it's a completely different circuit, with really high downforce, so everything can change."