Liverpool manager Jurgen Klopp could look to former club Borussia Dortmund to sign defender Neven Subotic in a cut-price deal and is also interested in taking former Arsenal captain Thomas Vermaelen from Barcelona.
According to German newspaper Bild (h/t talkSPORT), Subotic has been told he can depart the Westfalenstadion by BVB if his £4 million valuation is met, with the Reds seen as "front-runners" for his signature.
Hamburg are also interested in the centre-back, who was previously one of the most prized defenders in Europe under Klopp.
Subotic has asked to leave Dortmund in order to receive increased first-team opportunities, and the Bundesliga club have agreed to let him go, according to Bild.
Here is a video demonstrating Subotic's qualities:
The 27-year-old has plummeted down the pecking order under Klopp's replacement, Thomas Tuchel, and a reunion with his former boss will surely appeal to the Serbian.
Subotic has featured only three times in the German league this term, according to Squawka.com, and appears surplus to requirements after being one of Klopp's star performers in previous campaigns at home and abroad.
However, the defender was recently named as Opta's Bundesliga Player of the Day after an impressive but rare performance for his club against Hannover 96, a 1-0 victory:
Subotic said he was delighted to be back in BVB's starting XI after the match, via ESPN FC's Stefan Buczko:
Liverpool appear to be addressing their frailties in defence and as such would also like to attain Belgium international Vermaelen, who has suffered a myriad of injuries in recent seasons.
Spanish outlet Fichajes (h/t Charlie Phillippe of the Express) claimed that the Reds will battle Chelsea for the player's services, who has failed to impress at the Camp Nou after his £15 million switch in 2014.
Sports reporter Simon Collings alluded to past players who left Arsenal for Barca and may have regretted their decisions:
Klopp is desperate to add cover at the back, and both Subotic and Vermaelen have the necessary quality to strengthen Liverpool's poor defence.
The two players have vast experience in the Champions League and would improve the Anfield giants' overall stock.
However, despite being just 30, it is questionable whether Vermaelen would be a smart purchase given his injury record.
The money paid out by Barca to sign him was a huge outlay for a defender so often on the treatment table, and the Blaugrana have not seen a tangible return on their investment.
Joel Matip has already been confirmed as joining Liverpool at the end of the campaign, and Subotic would be a strong individual for the centre-back to partner in the back four in 2016-17.