Manchester City have made an improved second bid of around £60m for Arsenal’s Chile forward Alexis Sanchez.
The Gunners have already rejected a £50m bid from City for the player.
Sanchez, 28, who scored 24 league goals last season, is out of contract next summer and wants to play for City manager Pep Guardiola.
Arsenal have rebuffed all approaches for Sanchez, and would like City’s Raheem Sterling as part of any deal before Thursday’s transfer deadline.
But Guardiola is understood to want the Chilean as a straight purchase.
England forward Sterling, 22, has featured in all three of City’s games so far this season.
However, he is not guaranteed a starting role at Etihad Stadium following the summer arrival of Bernardo Silva from Monaco.
BBC Sport understands Sterling would be interested in moving back to his home city of London should he become part of the Sanchez deal.
Elsewhere, Borussia Dortmund have signed Manchester City’s 17-year-old English forward Jadon Sancho.
The highly-rated England youth international – who wanted to leave Manchester – had stopped training with the club to force a move.
But City did not give him permission to speak to any British clubs and a deal has now been agreed with German side Dortmund.
‘Arsenal in a world of trouble’
Sanchez joined Arsenal from Barcelona – where he played under Guardiola – in 2014 for a fee of about £35m.
He was granted an extended summer break this year after playing for Chile in the Confederations Cup and made his first appearance of the season in Arsenal’s 4-0 defeat at Liverpool on Sunday.
Earlier this month, Gunners boss Arsene Wenger said Sanchez would “respect” his decision to keep him for the last year of his deal and former Liverpool and England midfielder Danny Murphy says Arsenal cannot afford to lose him.
“If they let him go they’re in a world of trouble. They’re in a world of trouble anyway,” Murphy said on Match of the Day 2.
“He worked hard enough [at Liverpool] but as the game went away from Arsenal you could see him getting frustrated.
“His body language wasn’t good when he came off – in fact before he came off you could tell he was despondent.”
BBC Sport’s David Ornstein
Arsenal’s stance remains that they have no desire to sell, unless huge money and a player – most likely Sterling – are offered.
The final 12 hours of the transfer window are sure to test their resolve, and while in theory it could still go either way, the most likely outcome remains that Sanchez will stay and see out the final months of his contract.