Former Sauber driver Sergio Perez has sided with Giedo van der Garde in the Swiss team's case against the Dutchman.
Van der Garde won his case against Sauber on Thursday, meaning he is entitled to race for the team despite the Hinwil team having two contracted drivers - Felipe Nash and Marcus Ericsson - ahead of this weekend's Australian Grand Prix.
Van der Garde, signed as a test driver for 2014, claimed he had a contract to race with the team in 2015.
Perez, who drove for Sauber in 2011 and 2012, believes the way van der Garde was treated was wrong.
"It shouldn't be the way people should be treating drivers," Force India driver Perez told reporters on Thursday.
"They should respect drivers.
"We need this work and this career, so it's not fair when people are not treating you the way you should be treated."
It is still unclear what Sauber will proceed after its verdict was rejected by an Australian court.