The Williams Formula One team have boosted Indian Narain Karthikeyan's [Images] hopes of a reserve role next year by calling him back for more tests in Spain.

A team spokesman said Karthikeyan, who raced for Jordan this year as India's first Grand Prix driver, would test at Jerez on Wednesday and Friday after a first session with the former champions last Wednesday.

The 28-year-old Chennai driver did 49 laps with a best time faster than Germany's [Images] Nico Rosberg, who has secured the second race seat as team mate to Australian Mark Webber [Images].

This week's Jerez test will be the team's last until January 11 and only Karthikeyan and the two race drivers are scheduled to take part.

Although Karthikeyan appears to have moved into pole position for a slot that would allow him to drive Williams's third car in Friday practice at races next year, Denmark's Nicolas Kiesa has also been mooted as a candidate.

Kiesa, who competed for Minardi in 2003, was Jordan's test driver this year.

Karthikeyan told the Indian media after last week's test that working with Williams had been an eye-opener.

"Now I know why this team has done so well in Grands Prix," he said. "It's truly fantastic and I was able to give some valuable input to the team engineers."