Manchester United have endured a rocky end to the transfer period, with the club’s deal with Real Madrid involving goalkeeper David de Gea blocked due to paperwork being found to have been submitted a minute late.
Monaco are understood to be demanding £43m to allow Martial to make the move to Old Trafford.
The French international was bought by Monaco in 2013 for just £3.5m, but he experienced a breakout 2014-15 season with nine goals in 35 appearances.
It remains to be seen whether Man United will be willing to splash the cash, especially on such short notice.
However, the Red Devils are light on attacking options and manager Louis van Gaal is believed to be keen to bolster his attack before today’s 6pm transfer deadline.
Striker Wayne Rooney has looked like a shell of his former self during the beginning of the 2015-16 season, which has ramped up Man United’s efforts to sign another striker.