Mourinho: Costa unable to cope with fixture demand

Chelsea were held to a 1-1 draw by Schalke, who they twice beat 3-0 last term, after Cesc Fabregas' 11th-minute strike was cancelled out by Klaas-Jan Huntelaar. Costa, who has scored seven goals in his first four Premier League games following his £32million summer move from Atletico Madrid, came off the bench but was unable to find a winner.

"Costa has a problem," said Mourinho of the striker, who scored a hat-trick in Saturday's defeat of Swansea. "If he has one week to let the muscle recover he can start a game. Playing on Saturday, three days is not enough for him to recover. It was not to protect for the game Sunday (at Manchester City) it was because today he was not in condition to start the game."

Costa limped out of last season's Champions League final with Atletico with a hamstring problem and the injury recurred while on international duty earlier this month with Spain.

"He played here one match and he was perfect," Mourinho said. "He went to the national team and after the game against France he came back to us injured. He came to us (from Atletico) and he was completely fine. He had a problem again in the national team, not with us. Now we have the problem and now we have to resolve the problem the best we can.

"Today he was not in condition to play. Sunday we believe he is. Next week against Bolton (in the Capital One Cup) for sure he isn't. We have to manage the situation until the moment he's completely fine. If today he starts the game, for sure he cannot play on Sunday. We have to go step by step."

Diego Costa is a devastatingly good striker, so Mourinho’s preference to play him whenever he can is understandable. However, would it not make sense to rest him for three to four weeks to allow the injury to fully recover? Surely if there is a weakness in that muscle the Spaniard is risking pulling or tearing it every time he plays? The frustrating thing for Chelsea though is the fact that this is not their doing – the player was injured on international duty. It is little wonder why so many managers are reluctant to release their players for international duty.

Matt Law (Telegprah): Even with Diego Costa’s hamstring problems, the decision to bring Drogba straight into the starting line-up was a surprise, given the 36-year-old missed the Premier League victory over Swansea City with a swollen right ankle. It was hard to judge whether it was the troublesome ankle or just his age, but Drogba struggled to find the pace of the game and missed two good chances.

Dominic Fifield (Guardian): It took Andriy Shevchenko 41 games, and Fernando Torres 43, to register that many league goals for this club. It even took Didier Drogba 18. Yet Costa’s seamless adjustment to life in these surroundings merely confirms Mourinho’s insistence that Chelsea had been waiting for a player of his ilk to slot into an established system. They were in a holding pattern last season. Now their progression can gather pace.