Arsenal's decision to keep Alexis Sanchez at the club could cost as much as £140million, believes Arsene Wenger.

The Gunners reportedly rejected a £60m offer from Manchester City on transfer deadline day, with the club unable to conclude a deal for Monaco winger Thomas Lemar as Sanchez's replacement.

Arsenal allowed Alex Oxlade-Chamberlain to join Premier League rivals Liverpool for a reported £35m fee, but Sanchez and Mesut Ozi - both in the last year of their contracts - were retained.

And Wenger indicated it was a massive financial sacrifice for Arsenal to keep Sanchez at Emirates Stadium, despite the Chile forward intimating he wanted to move to play Champions League football.

"You take Sanchez into the final year of your contract, you sacrifice £60-£70m in income and then at the end of the season you will have to buy somebody for that amount of money," Wenger  said. "So it has a huge price. So at some stage you have to make a decision, you have to sacrifice one or two [players]."

Wenger reiterated his belief that the transfer market is going through a radical change as players such as Sanchez are increasingly happy to run down their contracts, while potential is even more valued than ever before as demonstrated by Barcelona's €105million capture of Ousmane Dembele.

"We have today 107 players in England who go into the final year of their contract," Wenger said. 'It's a complete rotation and change in the way people see their careers, for two reasons.

"One, all the players expect higher wages because they anticipate inflation; [and two] because the transfer market has gone up so much but clubs do not want to pay such high prices on transfers for players, who are good players but will not change [the club's] life.

"The amount of money is completely disconnected to reality and the truth. No matter how well you work on the football pitch you cannot make a player go from €15m to €150m. But the calculation between investment and what you can get back has gone. It's just: can you afford to buy or not?"