The pair, who will miss England friendlies with Germany and Holland this week, will almost certainly be absent for both legs of City’s Champions League quarter-final tie with Paris St Germain, joining captain Vincent Kompany who is also out for at least a month and whose absence was keenly felt in yesterday’s 1-0 defeat to United.
“Both of them have muscle injuries — Raheem his groin and Joe in his calf,” said Pellegrini.
“I don’t think a muscle injury will be fit in one week. Normally three or four weeks.”
Pellegrini appeared particularly sensitive to questions after the derby reverse, cutting short and walking out of one television interview, before insisting that the announcement in February that he is to leave the club in the summer has had no ill-effect on his players.
“I don’t think I lose any control,” said Pellegrini whose side has collected four points from the last available 18.
“The attitude of the team today reflects they are all involved in what we are doing. It is not the best way to finish the season but I am happy with the attitude.”
In the absence of Kompany, who injured his calf in the midweek Champions League game with Kiev, 35-year-old Argentinian Martin Demichelis endured a torrid game at the hands of Marcus Rashford and was replaced by Pellegrini before the hour mark.
United manager Louis van Gaal claimed victory had given his dressing room a real belief that, despite mounting criticism about his efforts this season, his side can finish in the top four.
“I have seen the dressing room after the match and it was fantastic, the happiness,” he said.
“I don’t think we have had a lot of luck this season and now we have a big result in Etihad Stadium, winning, one point behind, equal with West Ham, and more home matches than away matches. So you have a big possibility.
“I said before this game that we had to win because otherwise the gap was too big if they had won or drawn. Now we have to win our games.”