The Brazilian has emerged as a shock late transfer target for Erik ten Hag, with club officials in the Spanish capital to sound out the possibility of securing a deal before the transfer window closes.
Although Casemiro has been a mainstay in Real’s team – and part of five Champions League victories – the reigning La Liga champions would consider selling him.
Convincing the 30-year-old to leave may prove rather more difficult, though United have put together a package that is making him consider his options.
According to Marca, United have offered to almost double Casemiro’s current salary – which is believed to be around £180,000-a-week.
That would make him second only to Cristiano Ronaldo in United’s wage structure, while the length of the deal would keep him at Old Trafford until 2027.
His current deal with Real expires two years before that and Casemiro – who turns 31 in February – recognises that he is unlikely to ever receive another offer that is that long or that lucrative.
Further reports by Relevo claim Casemiro informed Real president Florentino Perez of United’s approach on Wednesday and is beginning to have his head turned by the offer.
While Perez reiterated that Real want to keep the Brazilian, they will not stand in his way if a suitable offer is made; a figure of €70million (£59m) has been mooted as the price point at which the Spanish champions would do business.
United have yet to formalise their contract offer for Casemiro or make official contact with Real, but will do so as soon as they have received a green light from the midfielder.
Although manager Carlo Ancelotti considers Casemiro a key part of his squad, the summer signing of Aurelien Tchouameni means they are incredibly well stocked in central midfield.
In addition to the former Monaco man, Real also have Luka Modric, Toni Kroos, Federico Valverde, Eduardo Camavinga and Dani Ceballos.
Cashing in on Casemiro – who cost just €6m (£5m) in 2013 – would bolster Real’s finances and give them a lot more wiggle room with regard to La Liga’s strict Financial Fair Play rules.
United boss Erik ten Hag, meanwhile, is believed to be eager to land a destructive, defensive midfielder to sit alongside a more creative playmaker and Casemiro ticks that box in a big way despite his advancing years.
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