Here is a look at how eight of them have fared so far.

Brazilian teenager Estevao scored a 95th minute winner as Chelsea inflicted a third consecutive defeat on Liverpool with a 2-1 win at Stamford Bridge on Saturday.

Alexander Isak scored his first Liverpool goal to inspire a 2-1 win against Southampton in the League Cup third round, while Chelsea survived a scare to beat third-tier Lincoln on Tuesday.

Manager Eddie Howe said Newcastle United are still adapting to life without Alexander Isak following the striker's transfer to Liverpool and called for patience as his new-look attack struggles to click into gear.

The opening matchday of the Champions League group-stage continues on Wednesday with a mouth-watering set of fixtures. Reigning champions PSG begin their title defence, Liverpool face familiar foes in Atletico Madrid, Chelsea revisit old memories in Munich, and last season’s finalists Inter travel to Amsterdam for a historic clash with Ajax. Early in the evening, Olympiacos host Pafos, while Slavia Praha take on Bodo/Glimt. 

Mohamed Salah scored a last-gasp penalty against Burnley on Sunday as Liverpool maintained their perfect record to climb back to the top of the Premier League.

Alexander Isak is not in Liverpool's squad for their Premier League match at Burnley on Sunday.

Pep Guardiola said Erling Haaland is "a little bit above" Alexander Isak as the Manchester City boss responded to Arne Slot's claim that Liverpool's new signing was "maybe the best striker in the world".

Liverpool striker Hugo Ekitike has welcomed the arrival of British record signing Alexander Isak and says he is excited about the challenge of competing for a place in the line-up with the Swedish forward.

Alexander Isak says he will be "forever grateful" to former club Newcastle following his British-record £125 million ($167 million) switch to Liverpool on transfer deadline day.

The Sweden striker is understood to have arrived at the club's training ground on Monday, with a protracted saga nearing an end.

Premier League champions Liverpool have agreed a deal to sign Alexander Isak from Newcastle United for a British record transfer fee, media reports said Monday.

Newcastle United's owners will not leave the Premier League club without a recognised striker if the protracted transfer saga involving Alexander Isak ends in the Swede's exit, manager Eddie Howe said ahead of a league meeting with Liverpool.

Newcastle manager Eddie Howe said on Friday his club cannot win in the saga over star striker Alexander Isak's future.

Newcastle great Alan Shearer has accused wantaway striker Alexander Isak of pouring "flames on the fire" of his row with the Magpies by accusing the northeast club of breaking promises.

Alexander Isak believes his departure from Newcastle is "in the best interests of everyone" after breaking his silence on the saga of the Premier League transfer window amid speculation over a move to Liverpool.

Newcastle got a worrying glimpse of life without Alexander Isak as they were held to a 0-0 draw in their Premier League opener at Aston Villa despite Ezri Konsa's dismissal.

Newcastle United manager Eddie Howe has admitted the cold war with wantaway striker Alexander Isak is far from ideal as his side prepare to start the Premier League season without their prolific goalscorer.

From Manchester United’s latest attacking addition to PSG’s defensive reinforcement, here’s a look at the latest moves and rumours in the transfer market:

Alexander Isak's future at Newcastle hangs in the balance after the Swedish striker was reportedly told to train apart from the rest of the squad on Wednesday.