Sauber will retain Japanese driver Kamui Kobayashi for 2011, the struggling Swiss team said Tuesday, as it is happy with his efforts in his first full Formula-One year.

"Kamui has definitely fulfilled our expectations in terms of his speed and fighting spirit," team principal Peter Sauber said. "Plus, his work with the engineers and his technical understanding has also developed very well.

"The experience he has built up over his first full season in Formula One will certainly stand him in good stead for 2011," he added in a statement. "And our aim is to give him a fast and reliable car from the outset next season."

Kobayashi, who turns 24 next Monday, has earned 21 points out of the team's 27 points so far this season and stood 12th in the drivers standings, compared with the last-but-one 17th place for teammate Pedro de la Rosa of Spain.

The team said their second driver for 2011 would be announced at a later date.

Kobayashi finished sixth at the British Grand Prix in July, equalling his best F1 finish, with Toyota in Abu Dhabi in his debut year.

"I feel very much at home in Peter Sauber's team and am very pleased we'll be working together again in 2011," the Japanese driver said.

He added: "However, for now I'm focusing 100 per cent on this year. There are still six grand prix weekends to go in 2010, and we'll be hoping to make up more ground."