Arsenal have suffered a major blow with reports suggesting that right-back Mathieu Debuchy could be out for up to three months.

According to the Mirror, the French defender, who sprained his ankle during the Manchester City clash, has significantly damaged his ankle ligaments, which could keep him out for a long period of time.

Arsene Wenger fears that his defender will be out at least until Christmas, putting Arsenal under major pressure in the defensive department.

Calum Chambers can cover for the injured Frenchman, but then the Gunners will be short at centre-back making Laurent Koscielny and Per Mertesacker the only recognised central defenders in the squad.

Spaniard Nacho Monreal becomes the first reserve centre-back after Wenger failed to replace Thomas Vermaelen, who departed for Barcelona in the summer.

The full extent of Debuchy's injury will be revealed after further scans on Monday.

With the transfer window closed, the 64-year-old manager may well look at the free agents available and bring in some cover.

The north London club were linked to free agent Colombian international Mario Yepes. Despite his age, the former Atlanta defender played a key role in captaining his country to the quarterfinals of the World Cup in Brazil this summer.

But they will have to look elsewhere, as the Colombian has been signed up by Argentine club San Lorenzo on a one-year deal.

Meanwhile, Jack Wilshere reveals that the Arsenal players are more determined this season and believes their high-pressing game is the reason for the Gunners having fought back after conceding an early goal.

"We had it [determination] last season but this season we're forcing it a bit. We're not accepting it, we're not just letting them play when we lose the ball, we want to win it back," Wilshere said, as quoted on Arsenal's official site.

"That first five seconds is important - we want to win the ball back in a dangerous position. You saw it with the first goal, we won it high up the pitch. Once we get behind the midfield with runners, teams can't live with us," the England international added.