It was expected a race seat for the teenager was part of Sauber's 'Russian rescue deal', but in fact Sirotkin will only be the test driver in 2014.
18-year-old Sirotkin told the Russian website f1news.ru that he supports Sauber's decision.
"In my opinion, it's the best option for my development -- to continue in the World Series by Renault and be third driver for a formula one team," he said.
"The (Sauber) contract doesn't say how often I'll drive the car on Fridays, but the position of third driver does include visits to the grands prix."
Asked specifically about the participation in Friday morning practice sessions, he added: "I have no doubt that one of them will be the grand prix in Sochi.
"We are also talking about testing for the super license. There is not really a rush, so it should be done either before the start of the season, or at the very beginning."
It sounds unlikely, therefore, that Sirotkin will take part in Sauber's official winter testing programme.
"It's hard to say," he admitted. "There is a chance, of course, but everyone is going to be developing completely new technology and so there may be some problems that need to be fixed.
"So I don't know what the team's decision will be."