Arsenal's defensive linchpin Gabriel dos Santos was injured in a friendly match in Brazil and is feared to be out for up to two months, casting a shadow over Arsenal's title challenge this season.

The 27-year-old center-back was substituted midway through Brazil's 2-0 victory over Senegal due to thigh discomfort, and the sight of him in obvious pain greatly worried Arsenal fans.

Reports indicate that Gabriel's injury may be more serious than initially thought, and he is likely to be out until January 2025, almost certainly ruling him out of this weekend's North London derby. Arsenal are still assessing the situation and are expected to confirm the exact recovery time in the coming days.

So far this season, Gabriel has started in every Premier League and Champions League match, forming one of the league's most solid center-back partnerships with Willian Saliba. Arsenal have conceded only 5 goals in their first 11 Premier League games and lead the table by 4 points, making Gabriel's crucial role in the team's system undeniable.

Gabriel's injury comes at a particularly bad time for Arsenal. The team faces a series of tough matches in the weeks following the international break, including against Tottenham, Bayern Munich, and Chelsea. Without their key center-back, Arsenal's defensive stability will be severely tested.

Currently, Cristian Moscura and Piero Sincape are the main candidates for backup, while Riccardo Carafiori can also play as a center-back, which may bring tactical changes and give young player Miles Lewis-Skeley more opportunities to play at left-back.

In addition to Gabriel, Arsenal has several other key players currently sidelined with injuries, including Martin Ødegaard, Noni Maduk, Gabriel Martinelli, Kai Havertz, and Victor Dzekeresh. While they are expected to return soon, their availability for the derby remains uncertain.