A series of disappointing performances have put any chance of a shock return to Red Bull - whom he starred with before stints at Renault and McLaren - firmly out of reach.
The 34-year-old has shown glimpses of his talent at times, most notably during his superb drive to clinch fourth spot in the Miami sprint race.
With just nine seats now up for grabs following the recent contract extensions given to Sergio Perez and Yuki Tsunoda - Ricciardo's RB team-mate - time is running out for the star to prove he deserves his place on the grid.
Speaking on the Red Flags Podcast, Steiner has revealed there may only be two options left on the table for the Perth-born driver, with retirement an increasingly likely possibility.
"I think if he doesn't re-sign with RB, he retires," said the Italian.
When asked to predict the chances of a new contract being offered, the 59-year-old responded: "In the moment, it's 60-40 that he stays."