Explained: Why Thomas Partey wasn't picked to play for Arsenal against West Ham in Premier League London derby clash

When the Gunners' matchday squad for the Hammers clash was announced on Saturday afternoon, neither Partey nor Merino were in the 20-man group. The important duo would have certainly been included but now manager Mikel Arteta has explained their absence.

Arteta revealed that the two midfielders have been ruled out through injury but didn't reveal what those injuries are or the severity.

He told Sky Sports: "Unfortunately, they both picked up an injury and the game too early and they couldn't be part of the squad."

Arsenal keenly felt the injury absence of captain Martin Odegaard and their results suffered during his time on the sidelines. Before the West Ham encounter at London Stadium, they were nine points adrift of league leaders Liverpool, and having more players out injured will not help in their title bid.

It remains to be seen how long both Partey, who has been playing at right-back of late in the absence of the injured Ben White, and Merino will be sidelined for. After this match, Arsenal host Manchester United in the league on Wednesday.