Leeds United manager Jesse Marsch has had to endure a number of problems on the left of his backline since his arrival at Elland Road back in February, with Junior Firpo having struggled with both form and injuries ever since his £13m move to the club last summer, while stand-in left-back Stuart Dallas has also been sidelined since April with a fractured femur.

As a result, Victor Orta has been linked with a number of players in the position in recent months, with the likes of Torino's Ola Aina, Empoli's Fabiano Parisi, Valencia's Jesus Vazquez and Philadelphia Union's Kai Wagner all believed to be of interest to the Whites' director of football ahead of the opening of the January transfer window.

However, undoubtedly one of the higher profile names believed to be on the Spaniard's shortlist of left-back targets this winter is Borussia Dortmund star Raphael Guerreiro, the 28-year-old defender who has been a key part of BVB's backline ever since his move to Germany from FC Lorient back in the summer of 2016.

And, with the Portugal international's current contract at Signal Iduna Park set to expire at the end of the current campaign, Leeds will be able to open pre-contract negotiations with the full-back upon the turn of the year ahead of a potential move on a free transfer next summer, or try to tempt the Bundesliga side into a sale with an offer in the January transfer window.

Either way, considering just how impressive Guerreiro has been for Dortmund over the last year, Orta managing to convince the 28-year-old of a move to Elland Road this winter would represent a massive coup for a club of the Whites' current stature.

Indeed, according to FBref, the £17.5m-rated talent ranks in the top 4% of full-backs of Europe's big five leagues for non-penalty goals per 90, in addition to the top 5% for non-penalty xG, the top 6% for shots, the top 25% for assists, the top 19% for xAG and the top 20% for shot-creating actions over the past 12 months - demonstrating just how deadly Guerreiro is in the final third.

The £59k-per-week flanker also ranks in the top 11% of full-backs for passes attempted per 90, as well as the top 17% for passes completed, the top 7% for progressive passes, the top 13% for dribbles completed and the top 25% for touches in the opposition penalty area over the last 365 days - highlighting how impressive the defender is in possession of the ball.

Furthermore, while it is undeniable that the Portuguese star is primarily a forward-thinking full-back, he still returns impressive defensive metrics, with the left-footer making an average of 1.5 tackles and 1.4 interceptions over his 12 Bundesliga appearances this season, while also making an average of 1.8 tackles and 2.0 interceptions over his four Champions League fixtures this term.

As such, with Guerreiro not ranking below the top 25% of all full-backs in Europe's big five leagues in any attacking metric, in addition to the "unreal" left-back appearing extremely solid in a defensive capacity, the argument that Orta simply must move for the 28-year-old this winter is an easy one to make, as Guerreiro would be an unbelievable addition to the Leeds defence.