Arsenal will go into transfer deadline day on tenterhooks over Alexis Sánchez, with Manchester City hopeful that an improved bid will persuade the London club to sell their star player.

Arsenal have softened their stance slightly over Sánchez in the past 24 hours or so and City feel that they have been given some encouragement in their summer-long pursuit of the striker. But it would still take a huge offer to get the deal over the line and, more significantly, Arsenal would have to bring in a replacement player, which promises to be complicated.

They have an interest in Monaco’s left-sided attacker Thomas Lemar, for whom they have made three unsuccessful bids this summer – the most expensive of which was worth €50m. Last Thursday, Arsène Wenger described the deal as being “dead” because Monaco had “closed the door”. If Arsenal could somehow prise it open and land Lemar, the 21-year-old France international who is also wanted by Liverpool, they could then be receptive to City’s overtures for Sánchez – who has one season left on his contract and wants to go to the Etihad Stadium.

Monaco have been steadfast in their refusal to do business over Lemar and it could be that Arsenal have to stretch themselves to something around €80m simply to make them consider the sale.

City intend to make a persuasive pitch for Sánchez, having seen an opening offer of £50m rejected on Tuesday. It is likely to take £70m or more to locate Arsenal’s tipping point on Sánchez but, as City have often proved, they have the financial means to break through any impasse. Significantly, after Tuesday’s negotiations, they believe that there is a tipping point.

Pep Guardiola worked with Sánchez at Barcelona during the 2011-12 season and he has made it plain to the City hierarchy that he wants a reunion with him. They are keen to oblige. Raheem Sterling, the City forward, was mentioned on Tuesday as a possible makeweight in the deal but that will not happen. Sánchez is in Chile, preparing for his country’s World Cup qualifier against Paraguay on Thursday night. Wenger has agreed to let Alex Oxlade-Chamberlain join Liverpool for £40m while he will try to move out Lucas Pérez and Joel Campbell on deadline day. The latter does not want another loan but he might have to accept such a move. Shkodran Mustafi is set to stay at Arsenal, after talks over a possible move to Internazionale broke down.

A move for Jean Michaël Seri, the €40m-rated Ivory Coast international who saw a proposed move to Barcelona collapse last week, is now not expected to materialise despite Wenger being keen to sign a long-term replacement for Santi Cazorla.