Ryan Giggs would be worth £2 billion in the modern transfer market, former Manchester United team-mate Roy Keane outlandishly claimed.
Neymar made a £198 million (€222m) move from Barcelona to Paris Saint-Germain earlier this month, more than doubling the previous world-record fee.
With Everton buying Gylfi Sigurdsson from Swansea City for £45m and Marko Arnautovic swapping Stoke City for West Ham in a £24m deal, ex-United captain Keane is bemused by the figures now involved.
The 46-year-old suggested his Old Trafford colleagues would be worth 10-figure sums if they were available on the current market.
"Ruud [van Nistelrooy] would be worth a billion. [David] Beckham, a billion. Giggsy, two billion," said Keane.
"It's mind-boggling, it really is. The figures out there now for players - it's not the player's fault, it's the market, the market value of players.
"It's mind-boggling - especially for the average players. If ever there's a time to be a professional footballer, it's now - average players are going for £35m. My goodness.
"The really brilliant players are going for big money. When average players are going for £30m-£40m, it does make you scratch your head."
Asked what he would be worth, Keane jokingly replied "£3.75 million" - the amount United paid to sign him from Nottingham Forest in 1993, then a British record transfer fee.