Manchester United star Sanchez is under pressure to deliver at Old Trafford after enduring a torrid campaign last term.
The Chile international signed from Arsenal back in January but managed just three goals.
Express Sport understands Manchester United pay Sanchez £300,000 a week, making him the club’s highest earner ahead of midfielder Paul Pogba.
But Thompson, speaking on Sky Sports, must have been joking when he said that Sanchez pockets a staggering £900,000 a week.
When Geoff Stelling was talking about United’s heavy spending recent years, Thompson quipped: “And £900,000 a week for Sanchez.
“But they did not pay a fee for him.”
Thompson was clearly irked by Jose Mourinho’s criticism of Liverpool, accusing the Merseyside giants of trying to buy their way to Premier League glory.
The Red Devils boss said: “I think Liverpool are trying to buy the title, but when I say buying I mean ‘buying’ with amazing investment.
“Chelsea has a fantastic squad, City have a fantastic squad too.”
Thompson then said: “Pot and kettle.
“Oh my goodness. You always buy what you can afford and it’s net spend at the end of the day.
“Our net spend to what Mourinho’s net spend is is massively different.
“How can you say that? Is he just trying to wind up everybody because this is Jose?
“Liverpool trying to buy the title? Oh my goodness.
“I’d accept that from a few other clubs and their managers, but not from Jose about Liverpool.
“Oh for goodness sake, just because we spent money this summer.
“It was an absolutely outrageous comment from Jose Mourinho, who’s bought titles wherever he’s gone.”