Barcelona are considering a January swoop for former Chelsea defender Branislav Ivanovic, Goal understands, as they seek to bolster their backline.
The Spanish giants are unsure if centre-back Samuel Umtiti will be fit to play in the new year following treatment on a knee injury.
As such, they are lining up a move for a defender with the profile of a 'veteran', with Zenit centre-back Ivanovic fitting the bill.
The ex-Serbia international is 34, and has been with Zenit since 2017, when he joined the Russian club from Chelsea.
A trophy-laden career has seen him win three Premier League titles, three FA Cups, the Champions League and the Europa League, as well as a Russian Cup with Lokomotiv Moscow.
Barca are thus attracted to the possibility of acquiring Ivanovic on a short-term deal, given that they are hopeful of signing Matthijs De Ligt from Ajax next summer.
De Ligt is widely regarded as one of the best young centre-backs in the world, and at the age of 19 is wanted by a clutch of clubs.
Juventus have entered the race to sign the Dutchman, along with Manchester City, and it remains to be seen if a bidding war will erupt.
Barca see the player as the next Gerard Pique, but De Ligt is under contract until 2021 - with Ajax having the option to extend that for a further year - and appears in no rush to make a decision over his future.
Nevertheless, Barca do not have the money to sign a big-name centre-back in January, and are also considering a move for Unai Nunez of Athletic Club.
He is 13 years younger than Ivanovic, but he too would not present a barrier to the potential signing of De Ligt, with Thomas Vermaelen's anticipated departure at the end of the season meaning Barca will have to recruit a new defender next summer.
At the same time, both City and Barca are also interested in De Ligt's Ajax team-mate Frenkie De Jong.
The Spanish league leaders are unwilling to match what City are prepared to pay for De Jong, however, and have accepted that their only remaining hope of warding off the English champions is if the Dutchman insists that he wants to move to Camp Nou to play with Lionel Messi.
But Blaugrana officials do not expect his desire to play with the Argentina international to be decisive in the transfer.
City are prepared to pay €70 million (£62m/$80m) plus €20m (£18m/$23m) in bonuses to sign a player regarded as a wonderkid.