But when the 2014 season began without Sirotkin, Sauber team boss Monisha Kaltenborn told the Russian website f1news.ru that "Everything is going according to plan".
"He has a (Formula Renault 3.5) seat with Fortec, I am sure he can get great results, and then we'll think about the next step," she added.
The next step could be an appearance on Friday morning in Sochi later this year, as Sirotkin's native Russia hosts its inaugural grand prix in October.
"We will certainly examine this possibility," Kaltenborn said.
"But for this, first of all he needs a superlicense. That's what we're working on now -- thinking about how we can make this possible."
According to 18-year-old Sirotkin, he will work on qualifying for the mandatory FIA credential at one of the post-race in-season tests, in Bahrain, Barcelona or Silverstone.
"In the coming months there will be the official formula one tests and that's where we plan to get it," he told the Russian broadsheet Izvestia.
"I will need to drive about 300 kilometres and be competitive. When we have it (the superlicense) in our hands, then we will talk about the Fridays," Sirotkin added.