Arsenal goalkeeper Petr Cech is a doubt for the north London derby against Tottenham due to a calf injury.
The 35-year-old was withdrawn after 70 minutes of Arsenal's 5-1 win over Everton on Saturday and the problem is still troubling him.
According to his manager Arsene Wenger, Cech has not trained at all this week and could now miss the crucial clash with Spurs on Saturday.
That would mean back-up goalkeeper David Ospina would take his place at Wembley.
Wenger said: "Cech is doubtful. He has not trained so I don't know.