Laurent Koscielny Returns to Arsenal Training Ahead of Manchester City Game

Arsenal captain Laurent Koscielny has returned to training and could be fit to face defending Premier League champions Manchester City at the Etihad Stadium on Sunday. 

Koscielny missed Tuesday's 2-1 home win over Cardiff City after suffering what was feared to be a broken jaw in their 3-1 FA Cup defeat to Manchester United on Friday. However, the Gunners released a fitness update on Friday confirming the captain had resumed full training:

Shkodran Mustafi and Nacho Monreal deputised at centre-back for the win over the Bluebirds, but a trip to the Etihad to face Pep Guardiola's side poses a greater challenge to Arsenal's back line.

United striker Romelu Lukaku unintentionally stepped on Koscielny's face during Arsenal's fourth-round defeat last week, leading Arsenal manager Unai Emery to suspect he had fractured his jaw, via Hayters TV:

Fortunately for the Gunners, the diagnosis was not as bad as first feared, although the injury update also detailed centre-back Sokratis Papastathopoulos isn't expected back in action until late February. 

Koscielny himself has said his initial fear was that his jaw was broken, which may not have surprised many given the nature of Lukaku's contact, per sportswriter Charles Watts:

Monreal has proved himself competent at centre-back both under Emery and his predecessor, Arsene Wenger, but Arsenal will need their best players available to stop the likes of Sergio Aguero, Leroy Sane and Raheem Sterling.

Ainsley Maitland-Niles, who has played most of this season as a right wing-back, and Henrikh Mkhitaryan are being assessed in the build-up to Sunday's away trip.

Arsenal's defence has been ravaged this season, with right-back Hector Bellerin and central defender Rob Holding expected to miss the remainder of the season after each suffering anterior cruciate ligament injuries.

Former Arsenal midfielder Stewart Robson said after the home defeat by United that while his old club may have hired a new manager in Emery, they still exhibit the same, familiar defensive flaws, via ESPN FC:

Sunday's visit to City will be the first of three consecutive road games for the Gunners, who will travel to Huddersfield Town before facing BATE Borisov in the first leg of their UEFA Europa League last-16 showdown.

Arsenal sit fourth in the Premier League—level on points with Chelsea and two points ahead of Manchester United—and are at risk of falling out of the UEFA Champions League spots if they lose at the Etihad.