Despite the winter transfer window being closed, Manchester United continues to be linked with players. The likes of Elliot Anderson of Nottingham Forest and Carlos Baleba continue to be mentioned when it comes to who will be the Casemiro replacement.

It’s always important to have targets in mind ahead of the summer. If you wait too long, other clubs will have taken advantage and will simply get there first, leading you to look at players who are not first-choice targets.

One other player to be linked with United is Borussia Dortmund central defender, Nico Schlotterbeck, who has consistently impressed with his performances for the German side. 

High-profile German media outlet BILD has reported that United have made the 26-year old their "number one target" to strengthen the defence in the summer transfer window. 

As it stands, the defender will only have 12 months remaining on his Dortmund contract this summer, and the player has shown no signs of wanting to extend his current deal, at least not yet. 

As you may expect, Bayern Munich has shown interest in Schlotterbeck, but it has been reported that BVB would much rather sell him abroad than to a domestic rival. Also, Bayern defender Dayot Upamecano - who was out of contract this summer - has now signed a new deal at the club, perhaps negating the need for a new external signing. 

This could give United, perhaps not a free run at Schlotterbeck, but certainly a more straightforward pass, should they end up trying to pursue a deal for the German international. 

Since joining Dortmund, he has built a fine reputation for his ability on the ball. So much so that at some point, he even began taking corners for the team last season, and to a degree of success, too. 

He often operates on the left side of a back three, but also as the 'libero' in the middle of the three, too. That said, he has played in a back four both at club and international level. At times, he has filled in at left back, too. 

This would be quite interesting because Lisandro Martinez has fairly recently returned from injury and has looked very good. They are similar profiles - left-footed, ball-playing central defenders. It would be hard to imagine both in the starting XI, with both being left-footed and just in general with both being similar type defenders. 

Still, a very good player, so let's see. 

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