Arsenal have added Jurrien Timber to their Champions League squad ahead of their last-16 tie with Porto later this month.
The 22-year-old defender joined the Gunners from Ajax for a reported £38m last summer, penning a long-term contract until June 2028.
However, the highly-rated Dutchman sustained an ACL injury on his Premier League debut back in August last year and has since spent a lengthy period in rehabilitation after undergoing surgery.
Manager Mikel Arteta admitted last month that Timber still needs more time to recover from his injury before making a return to training.
"Unfortunately, that's a very long-term injury," Arteta told reporters. "He is doing really well but he is still far from being fit to train with the team, or something to compete with the team so we don't expect him back anytime soon."
However, Arsenal have dropped a hint to suggest that Timber could return before the season comes to a close, as they have included the defender in their Champions League squad for the second half of the campaign.
Timber was left out of Arsenal's initial Champions League squad for the first half of the campaign and subsequently missed each of the Gunners' six group-stage matches.
The Gunners collected 13 points from four wins and one draw in Group B to qualify as group winners ahead of PSV Eindhoven, Lens and Sevilla.
Arsenal will travel to Lisbon to take on Porto for the first leg of their last-16 tie on February 21, before welcoming the Portuguese side to the Emirates Stadium for the second leg on March 12.
Should Arsenal beat Porto over two legs, 90min reports that Timber could be in a position to return to the first-team fold in time for the Champions League quarter-finals in April.
Meanwhile, injured trio Gabriel Jesus, Thomas Partey and Fabio Vieira have all retained their places in Arsenal's Champions League squad, but Lino Sousa has been replaced by Timber following his permanent transfer to Aston Villa.
There is no sign of Marquinhos in Arteta's squad, despite being recalled from his loan with Nantes last month; the winger – who is currently with Brazil Under-23s at the CONMEBOL qualifiers ahead of this summer's Paris Olympic Games – has been linked with a possible loan switch to Fluminense.
Arsenal's 25-man Champions League squad in full:
Goalkeepers: Aaron Ramsdale, David Raya, James Hillson
Defenders: William Saliba, Ben White, Gabriel Magalhaes, Jurrien Timber, Jakub Kiwior, Cedric Soares, Takehiro Tomiyasu, Oleksandr Zinchenko
Midfielders: Thomas Partey, Martin Odegaard, Leandro Trossard, Jorginho, Fabio Vieira, Mohamed Elneny, Kai Havertz, Declan Rice
Attackers: Bukayo Saka, Gabriel Jesus, Emile Smith Rowe, Gabriel Martinelli, Eddie Nketiah, Reiss Nelson body check tags ::