More than £3 billion ($4 billion) and 155 incoming transfers set high expectations across the Premier League this summer. Several recruits have settled quickly, but others have produced worrying initial returns that have left managers and supporters asking questions.

Everton’s Thierno Barry arrived from Villarreal after a season that yielded 11 goals and four assists. The 22-year-old joined for £27 million ($36 million) with time to adapt, but he remains behind Beto, has made two Premier League starts, nine appearances in total and is still searching for his first goal or assist for the club. On two occasions he was substituted early: at half time at Anfield and after about an hour at home to Brighton & Hove Albion.

West Ham’s £20 million ($26.7 million) signing Mads Hermansen began the campaign as Graham Potter’s first-choice goalkeeper but has endured a difficult start. The 25-year-old conceded 11 times in four appearances, sustained several high-profile errors and has dropped behind Alphonse Areola with Nuno Espírito Santo opting against an early recall.

Anthony Elanga moved to Newcastle for £55 million ($73.4 million) after scoring 18 goals for Nottingham Forest in 2024–25. The 23-year-old has made 10 appearances for the Magpies without a goal or assist and has oscillated between starting and the bench while competing with Anthony Gordon, Harvey Barnes and Jacob Murphy.

Jean-Clair Todibo’s permanent move to West Ham cost £32.8 million ($43.8 million) after an obligation to buy. He has fallen out of favour following disciplinary issues under Potter and is unlikely to figure under Espírito Santo.

James Trafford returned to Manchester City for £31 million ($41.3 million) but is now behind Gianluigi Donnarumma and has been restricted to the bench following a difficult display against Tottenham Hotspur.

Alexander Isak joined Liverpool for a Premier League record £125 million ($166.9 million) but missed pre-season after a strike. Arne Slot has eased him in, using him alongside Hugo Ekitiké, with the record signing yet to reach expected levels.

Newcastle paid £55 million ($73.4 million) for Yoane Wissa from Brentford, but a knee injury means he is yet to play for his new club and has only two competitive appearances since the end of last season.

Chelsea’s £51.5 million ($68.7 million) addition Jamie Gittens has made seven appearances and three starts without making a major impact. At Liverpool, Milos Kerkez arrived for £40 million ($53.4 million) to succeed Andy Robertson but has made a sluggish start, was bullied on his debut by Antoine Semenyo and was hooked in the first half against Burnley as he edged toward a red card.

It remains early and circumstances differ across clubs, but the opening weeks have provided enough evidence to raise concerns about several high-cost recruits.

Diego Costa returned to Chelsea on Saturday and did so in familiar fashion, picking up a yellow card after squaring up to Martin Škrtel during a charity friendly. The match ended with Liverpool claiming victory through a late Ryan Babel goal, but Costa’s presence dominated the conversation.

Several confrontations with Škrtel followed a physical challenge from Costa, with the clash culminating in a booking for a reaction that briefly overshadowed the charity context. The pair have a well-documented Premier League history: Costa received a three-match ban after being found guilty of stamping on Škrtel in 2015, and months later avoided punishment for what appeared to be a kick in Škrtel’s direction.

Their latest incident did not carry the same fallout. The two appeared to make up after the final whistle, an outcome Costa underlined with an Instagram post following the game.

Those familiar with Costa’s Chelsea career between 2014 and 2018 will recognise the temperament on display. The striker scored 59 goals in 120 appearances for the club, won two Premier League titles, and collected 32 yellow cards at Stamford Bridge without receiving a straight red.

“Of course, this guy [Costa] is still the same, we saw it!” former teammate Eden Hazard, who also featured in the game, reflected.

Costa has not played competitively since being released by Grêmio in January this year. His time at the Brazilian club included a notable sending off during a fitness-building Under-20 friendly for an on-field fight in September 2024. He finished his spell at Grêmio with eight goals in 26 games.

He has not formally retired, and whether he is actively seeking a new club remains unclear.

Chelsea have received a further fitness setback after Enzo Fernández withdrew from the Argentina squad with a knee problem.

Fernández played 78 minutes in Argentina’s victory over Venezuela, a game in which he recorded more touches and passes than any other player on the pitch. Argentina’s official X account announced on Saturday that he had been withdrawn from the squad because of an inflammation of the knee, adding his name to Chelsea’s growing list of absentees.

The midfielder was already expected to miss Argentina’s second friendly with Puerto Rico, with BBC Sport’s Nizaar Kinsella reporting that he would not play in that match. Given that information, an early return to west London for further assessment and treatment makes practical sense.

Chelsea had entered the international break dealing with multiple fitness concerns. The squad for the club’s last-gasp win over Liverpool had been weakened by absences that included Levi Colwill, Wesley Fofana, Cole Palmer and Liam Delap. In the same victory, Josh Acheampong and Benoît Badiashile also suffered fitness problems.

Head coach Enzo Maresca will now be monitoring Fernández’s situation closely ahead of the club’s return to Premier League action. Chelsea travel to Nottingham Forest next in the league, and the manager will be hoping that the knee inflammation is not a significant issue after what has already been a week of unwelcome injury news.

For now the club must wait for assessments following Fernández’s return, with the immediate priority likely to be reducing inflammation and evaluating how soon the midfielder can rejoin team training without risk of further setback.