Mauricio Pochettino has backed Enzo Fernández, Mykhaylo Mudryk and Raheem Sterling to live up to their expensive price tags, but Chelsea’s new head coach warned his struggling stars that there will be no excuses to underperform next season. Pochettino is keen to lift the mood at Stamford Bridge and he is aware the amount of change at Chelsea has made it difficult for new signings to settle. Fernández and Mudryk have been inconsistent since joining for huge fees in January, Sterling has not found his best form since his £47.5m move from Manchester City last summer and Marc Cucurella has also been disappointing since signing from Brighton for £62m. “Now is a new start,” Pochettino said. “They need to show their real quality. But we need to create a platform for them to feel comfortable and to create the space for them to perform and improve. These players were arriving in difficult circumstances and it’s a great challenge for us, because we love to work in this way. We need to give them the opportunity to show they are able to cope with pressure to play for Chelsea. “It’s not only responsibility of [the coach] always to feel [the mood] with everyone. The player has responsibility to try to adapt and have his own motivation and try to work really hard and let us to manage to try to achieve the very best.” Chelsea broke the British transfer record when they signed Fernández from Benfica for £106.8m. The Argentina midfielder had just won the World Cup but has not displayed his quality on a consistent level. “It was important now to rest a little bit because he was one year and a half playing, playing, playing,” Pochettino said. “It was arriving from Argentina to Portugal from Portugal to World Cup and from World Cup to England and never stop for one year and a half. He’s young and energetic but young players also need to rest and clean the mind and he arrived in Chelsea not in the best circumstances. “He is still young and needs to learn about the Premier League. Now he knows what it is to be a Chelsea player and knows London, and is communicating better and we are going to help in all these aspects.” Mudryk, who joined from Shakhtar Donetsk for £88.5m, will report for training on Monday week after representing Ukraine at the European Under-21 Championship. “It’s really important to spend time to talk,” Pochettino said. “I’m going to meet him before he comes to pre-season. I really like to see and to know him, and then to design the best strategy to help him to be at the level that Chelsea expect.” Chelsea finished 12th last season and did not see the best of Sterling, who struggled with his form and fitness. “We are talking about a really good player,” Pochettino said. “But sometimes it’s not easy for a player to adapt quickly and show the same performance that he maybe had at the other club. We need to reduce the number of people in the squad because it was so big. People need to find their space in the training ground, then in training, then in the team. “We can’t just blame the players. We need to see what is going on and why they are not performing in the way we expect. When all is clear, we cannot give excuses to them not to perform. We need to clean everything and say: ‘Come on – now it’s up to you, show me that you are ready to play for this club’.” Pochettino intends to hit the ground running but Chelsea still have problems to solve. They do not have a shirt sponsor and have not found a goalkeeper to replace Kepa Arrizabalaga. Some of Graham Potter’s backroom staff remain at the club and Chelsea have not found buyers for Romelu Lukaku and Pierre-Emerick Aubameyang. “I am not worried,” Pochettino said. “From tough situations you can become stronger. Different circumstances in the last few years put the club in this situation. That is why we are here – to try to fix things. I am not a person who will think too much about all these situations. I feel the responsibility but I am not worried.” Pochettino is set to hold talks with Levi Colwill over the centre-back’s future. Brighton had Colwill on loan last season and have already had a £30m bid rejected for him, with Chelsea keen to hand the defender a long-term deal. Chelsea are determined not to sell the England Under-21 international and do not want to include him as part of a deal for the Brighton midfielder Moisés Caicedo. However, Pochettino was asked if he needs to convince Colwill to stay. “I need to get a feel for him,” Pochettino said. “I need to hear what he has in his mind. What he expects. And then, of course, for him to listen to what I expect from him.”