Manchester United signed Sofyan Amrabat on loan as part of a hat-trick of arrivals at Old Trafford in the hectic final hours before Friday's transfer deadline, while Liverpool reportedly turned down a £150 million ($190 million) offer from Saudi Arabia for Mohamed Salah.
Manchester City swooped for Wolves midfielder Matheus Nunes in a £53 million deal after selling Cole Palmer to Chelsea and Tottenham landed Brennan Johnson from Nottingham Forest in the day's other major deals.
English top-flight clubs smashed their record for spending on new players during this window, with the total surpassing £2 billion for the first time, according to financial experts Deloitte.
"You've got that intensity of competition across the league. Whether that's competing for the title, competing for European places or just simply staying in the league, that's driving spending," said Calum Ross, assistant director in Deloitte's Sports Business Group.
"There are 10 clubs that have spent more than £100 million."
United left it late to get a deal done for midfielder Amrabat that will see one of the stars of Morocco's run to the World Cup semi-finals join from Fiorentina for a 10 million euro (£8.6 million) loan fee with the option to buy for a further 25 million euros next year.
Amrabat was joined by Turkish goalkeeper Altay Bayindir from Fenerbahce and Spanish left-back Sergio Reguilon, who was with Spurs, in joining the Red Devils on deadline day.
"I've had to be patient for this moment but I'm someone who always listens to my heart and now I am representing the club of my dreams," said Amrabat in a United statement.
Mason Greenwood departed United on Friday, joining Spanish side Getafe on loan.
The club and Greenwood mutually agreed for the forward to continue his career elsewhere after he faced allegations of abuse involving a young woman.
- 'No doubt' Salah stays -
But the Reds stood firm in the face of Al-Ittihad's attempt to lure Salah to Saudi.
"The position remains the same. Absolutely no doubt about that," Liverpool boss Jurgen Klopp said of the Reds' desire to keep the 31-year-old, who has two years left to run on his contract.
However, the Saudi transfer window does not close until September 7.
Treble winners City bolstered their midfield options after the departure of Ilkay Gundogan and a long-term hamstring injury suffered by Kevin De Bruyne by signing Portugal international Nunes.
"The opportunity to work under Pep Guardiola, one of the greatest managers ever, and alongside some of the best players in the world was something I simply couldn't turn down," said Nunes.
- Palmer chooses Chelsea project -
City cashed in on Palmer for an initial £40 million that takes Chelsea's spending on new players in just over a year under the club's American ownership beyond £1 billion.
Palmer agreed a seven-year contract with Chelsea, who could pay City an extra £2.5 million in add-on clauses.
The 21-year-old scored in both the Community Shield and UEFA Super Cup last month.
But Palmer, who helped England win the Under-21 European Championship this year, has been convinced by Chelsea's plan to invest heavily in young players.
"I’ve joined Chelsea because the project here sounds good and because of the platform I will have to try to showcase my talents," said Palmer.
"It is a young and hungry squad and, hopefully, we can do something special here."
Tottenham splashed out some of their Harry Kane cash on Johnson for a £47.5 million fee.
Forest used that money to strengthen their squad in a number of areas as Greek goalkeeper Odysseas Vlachodimos, midfielder Nicolás Domínguez and former England winger Callum Hudson-Odoi all joined in the final hours of the window.
Fati was regarded as one of the most promising talents in Europe when he burst onto the scene four years ago before injuries have halted his progress.
"This is a great deal for all of us. I am sure Ansu will help us to reach a new target and we can help him get back to the level he deserves to be," said Brighton boss Roberto De Zerbi said.