Pep Guardiola's Man City nightmare continues: Ruben Dias out for up to one month with injury sustained in derby loss to Man Utd

Dias, who has featured in 19 matches across all competitions this season and started in 12 of City’s 16 Premier League games, picked up a muscle injury late in the match against United. He had missed five matches in November due to a calf injury but it had been smooth sailing for the Portuguese defender until that setback.

Adding to Guardiola’s selection concerns is uncertainty over the availability of goalkeeper Ederson. The Brazilian is a doubt for the Villa clash and in his absence Stefan Ortega, who started three Premier League matches earlier this season when Ederson was benched, could once again take his place between the posts.

At a press conference on Friday, Guardiola said, "Ruben is out for a long time and Ederson, I don’t know if he will be ready for tomorrow. It will be three to four weeks (for Dias). In the 75th minute against United, he felt something muscular, he is so strong and wanted to stay on the pitch and now he is injured."

Despite the disappointing news regarding Dias and Ederson, Guardiola provided an encouraging update on defenders John Stones and Manuel Akanji. Both players have resumed training and may be available for selection against Villa.

"Manuel and John, they are back training the last two days, so that’s good for us," he said. "I don’t know yet (if they will start on Saturday). Yesterday (Thursday), was their first training session."

This injury means Dias will miss several important games, beginning with Saturday’s trip to Aston Villa. The defender is also ruled out for City’s Boxing Day clash against Everton at the Etihad, a trip to Leicester on December 29, and the home fixture against West Ham on January 4.