But the Italian giants are talking him up, with Ferrari team principal Mattia Binotto saying: "I think Mick through the season did well. He improved himself, not only in terms of consistency, but also in terms of speed.
"If I look at the last races, he was a lot closer to the cars ahead, while Haas didn't really develop the car at all.
"So the fact that he was closer is he proved that he had a good improvement on the speed itself."
Schumacher will keep racing for Haas, but switch if Charles Leclerc or Carlos Sainz are unavailable.
The elevation is not the only news concerning Schumacher, who has also been revealed as the most crash-prone driver in F1 this year.
According to a report in The Times, he notched up just over $7 million in repairs, pipping Leclerc and new champion Max Verstappen.
Red Bull's Verstappen hit the $6.5m mark, more than three times the repair bill racked up by his great rival and deposed champion Lewis Hamilton.