Manchester United's bid to sign a new centre-back before the transfer window closes on Thursday is about to get very interesting.

Harry Maguire, Toby Alderweireld, Yerry Mina and Jerome Boateng are the four players Jose Mourinho has reportedly been tracking in recent days.

And the latest on each of them is as follows.

Leicester City maintain that they don't want to sell Maguire, who is valued at a staggering £75m following his performances for England at the World Cup.

However, the Foxes are on the verge of signing centre-back duo Caglar Soyuncu and Filip Benkovic for £40m, so that could pave way for Maguire to join United.

As for Alderweireld, Tottenham have stuck to their guns by also demanding £75m for the Belgian despite him being in the final year of his contract.

It's claimed United will make one final 'take it or leave it' offer of £40m, but it's very likely that will be rejected.

MAKING THEIR MOVE

Mina's situation is far less complicated. Barcelona want £40m for the Colombian and United recently tested their resolve with a £35m opening bid.

And then there's Boateng, who's been linked with a £45m move to Manchester but has now told Mourinho over the phone that he's flattered but not interested.

Boateng's response to United's interest was class and now more details have emerged from his conversation with Mourinho.

According to Sky Sports and the Guardian, the German's real reason for not wanting to join United is because he doesn't think they're good enough to win the Champions League.

Boateng wants a second Champions League title and he feels he has a better chance at Bayern Munich, which even United fans understand.

Here's how they've been reacting to Boateng's reason for rejecting them.

So it's down to Maguire, Alderweireld and Mina. Due to his quality and world-class status, Alderweireld is undoubtedly the superior option for United.

But with Tottenham holding firm, Maguire's experience in the Premier League would be preferred to Mina, who barely played for Barcelona last season.