Manchester City could be without record goalscorer Sergio Aguero for another month, manager Pep Guardiola has suggested.
Aguero, playing just his third match since recovering from the knee operation he had in June, sustained a muscular problem and was withdrawn at half-time in Saturday's Premier League draw at West Ham.
That has ruled the 32-year-old out of Tuesday's Champions League Group C clash at Marseille, with the club unsure for how long the player will be sidelined.
Guardiola said: "It depends on the injury. When it is minimum it will be 10-15 days. If it is longer it will be three weeks to a month. I don't know.
"When you are four or five months out (with) knee problems, always you have a risk when you come back.
"We tried to handle it as well as possible, just 50-55 minutes a game, but it was not enough to get fit for the next games. He will be back as soon as possible."
City have had a difficult start to the campaign, dropping points in three of their five Premier League games and dealing with a lengthy list of casualties.
Aguero's absence leaves City without an established centre forward as he joins fellow striker Gabriel Jesus on the sidelines.
To compound matters, Fernandinho, Benjamin Mendy and Nathan Ake also miss the behind-closed-doors encounter at the Stade Velodrome, although Aymeric Laporte has travelled and Kevin De Bruyne is back in contention to start.
Guardiola pointed out many teams will have to contend with similar problems due to the intensity of this season's pandemic-affected fixture schedule.
He said: "We are not an exception compared to the other teams in Europe. We're on the same schedule. Now it is recovery, preparation, recovery and preparation, recovery and preparation.
"We don't have time to practise much. Everyone got the statistics – in the Premier League, we have 47 per cent more muscular injuries than the same period last season. It's not just about City, it's about everyone.
"If the people can reflect on this and the guys to protect the players it will be good for the future, if we don't it will increase. Nowwe have to protect the players as best as possible. The strongest ones will survive, the others will fall down."
City strengthened their defence with Ake and Ruben Dias in the summer and also brought in a winger in Ferran Torres. The injuries to Aguero and Jesus, however, have raised questions over whether the club should also have tried to sign a striker.
Guardiola said: "Maybe. We considered it, we thought about another type of striker but we could not.
"If you decide to buy a striker, it has to be a striker in the league of Gabriel and Sergio, but we cannot afford it. That is the reality.
"We thought, 'OK, Sergio is back' and we didn't expect Gabriel to be injured, but sometimes it happens."
After opening their latest Champions League challenge with a 3-1 victory over Porto, City will hope to put themselves into an early position of strength in Group C with victory in France. Marseille were beaten by Olympiacos in their first game.
Speaking at his pre-match press conference, Guardiola said: "It's important to qualify. We played a tough game first, now we have the second one. Always in France it's difficult with the physicality but it's a good chance to step forward in the group stage."
