Arsenal have identified Manchester United's Eric Bailly and Chelsea veteran Gary Cahill as potential January replacements for Rob Holding, sources have told ESPN FC, following the defender's cruciate ligament injury.
Holding, 23, is expected to be sidelined for the rest of the season after rupturing his anterior cruciate ligament during the 2-2 draw against United at Old Trafford last week and although Unai Emery's team have since been boosted by the return to fitness of Laurent Koscielny following a six-month absence with an Achilles tendon injury, the club are determined to add an experienced centre-half to maintain necessary depth in their defensive options.
Bailly faces an uncertain future at United after falling out of favour under Jose Mourinho this season.
The 24-year-old initially made a big impact at Old Trafford following his £30 million move from Villarreal in June 2016, but injuries and loss of form have halted his progress, and Mourinho now favours Chris Smalling, Victor Lindelof and Phil Jones ahead of the Ivory Coast international.
Emery is known to be an admirer of Bailly having watched his development at Espanyol and Villarreal during his time as Sevilla coach.
But despite Bailly's battle to persuade Mourinho of his worth at Old Trafford, sources have told ESPN FC that United would rather sell Argentina defender Marcos Rojo next month and keep Bailly, who is also interesting AC Milan, in the squad.
Rojo has made just two senior appearances this season and has no future under Mourinho, but Arsenal have no interest in the former Sporting Lisbon player, despite being made aware of his availability in January.
Cahill, meanwhile, is regarded as a possible short-term solution to Holding's absence, with the 32-year-old set to leave Chelsea on loan next month after being told he can move on by the club.
The former England centre-half is out of contract at Stamford Bridge at the end of the season, but any Arsenal interest could be complicated if Chelsea choose to block any move to a rival for Champions League qualification.