Paul di Resta and even Kamui Kobayashi have also been named as possible replacements.

CNN: Massa under more scrutiny in Montreal

Sauber have re-signed Japanese driver Kamui Kobayashi for 2011 but have not yet announced their second driver.

BBC: Jerome D'Ambrosio & Esteban Gutierrez win F1 test roles

Lotus' Kimi Raikkonen and Sauber driver Kamui Kobayashi complete the top ten line up, finishing seventh and eighth respectively.

CNN: STORY HIGHLIGHTS

Kamui Kobayashi of Sauber and Vitaly Petrov for Renault rounded out the point-scoring.

CNN: STORY HIGHLIGHTS

The BMW Sauber pair of Pedro de la Rosa and Kamui Kobayashi were among the first to go out, but they struggled for grip.

BBC: Lewis Hamilton fastest in Friday Australian GP practice

The switching of his investment has cast doubt over the future of Sauber's other driver this year, Japan's Kamui Kobayashi -- who has no major sponsor.

CNN: F1 star Perez gives Mexicans hope

Toyota's Kamui Kobayashi, who is deputising for the injured Timo Glock, was fifth, followed by Toro Rosso's Sebastien Buemi and Red Bull's Mark Webber, winner in Brazil last time out.

CNN: Kovalainen quickest in Abu Dhabi practice

There was still time for a late flurry as Toyota's Japanese rookie driver Kamui Kobayashi, who is once again deputising for the injured Timo Glock, moved up to third position before finishing fifth fastest.

BBC: Kovalainen top as McLaren shine

The early pace on Saturday was set by Kamui Kobayashi with 1:21.242, but Alonso supplanted him at the top of the times mid-morning when he dipped down to a 1:21.140 after 30 laps of running.

BBC: Nick Heidfeld heads Fernando Alonso at his Renault test