Italy's Jarno Trulli has warned his employers not to expect miracles when he makes his Toyota debut at this weekend's Japanese Grand Prix.
But Trulli, who left Renault by mutual agreement last month, said he was relishing the challenge of driving for Toyota at Suzuka on Sunday.
"It's not going to be an easy weekend," said Trulli, who won his first Formula One race in Monaco this year.
"When you jump in a new team and you go to race after three days testing it's not going to be easy. But I am motivated to do well. It's new adventure.
"It's a bit complicated because it's all new and it's a question of time to take the car to the limit."
Trulli insisted he felt no extra pressure making his first appearance for Toyota at the Japanese team's home Grand Prix.
"It doesn't matter where you are, what you are doing, there is always pressure," he said.
"It's part of the job. It's going to be a home race for Toyota and we all want to show good things. But obviously we know our limits."
Trulli will be joined at Toyota next season by Ralf Schumacher, who has had a frosty relationship with team mate Juan Pablo Montoya at Williams.
However, Trulli said he would be able to work cordially with the German.
"From the little experience I've had in testing (in Jerez), honestly, I can't see any problems," said Trulli.
"It depends on the way you approach people. We're not all the same. We have to deal with the positive and negative things. I'm a nice person but I'm sure not everyone likes me in the paddock."