Rumours suggesting Lewis Hamilton could switch to Ferrari may be powered by the money, according to key rival Red Bull's top Austrian official Dr Helmut Marko.
The speculation of contact between the seven time world champion and Ferrari president John Elkann was clearly the top story in Formula 1 on Tuesday.
"I think it's just a rumour," former F1 driver Ralf Schumacher told Sky Deutschland.
"Hamilton is very happy where he is right now," he added, referring to Mercedes. "And even Ferrari is a bigger question mark at the moment."
Schumacher says he has heard that at an internet Mercedes event in Stuttgart recently, 38-year-old Hamilton reassured the company that "he wants to end his career with them".
He also questions whether Mercedes boss Toto Wolff would be keen on swapping out Hamilton for Ferrari's reportedly disgruntled Charles Leclerc.
"Honestly, if you look at the error rate and the pure driving performance of Charles Leclerc and Lewis Hamilton, there is no doubt that Hamilton is the more consistent driver at the moment.
"I think his motivation is financial on the one hand, but success-driven on the other," said Schumacher.
"Even with a car that doesn't work at the moment, Mercedes is still often ahead of Ferrari. That's why I don't think Ferrari as an alternative makes sense."
Red Bull's Marko agrees - and he thinks he knows what is powering the Ferrari rumours.
"There are two things that really annoy Hamilton," he told f1-insider.com. "First, that he is no longer world champion and will find it difficult to win it again in the future.
"He knows there is no place for him at Red Bull," Marko added. "And whether Ferrari will be better for him on the sporting side is not set in stone."
But, like Schumacher, Marko also thinks there is a financial incentive behind the Hamilton rumours.
"Lewis is anything but happy that he is no longer the highest-earning driver in Formula 1. That is Max Verstappen now," said the 80-year-old.
"At least he could change that with Ferrari's help."
