Sky Sports claim that an agreement over a deal believed to be worth approximately £35m ($45.2m) was struck on Monday afternoon (28 August). Oxlade-Chamberlain, who is currently at St George's Park preparing for 2018 World Cup qualifiers against Malta and Slovakia, will now discuss personal terms as the defending Premier League champions seek to force through a move before Thursday night's transfer deadline.
Like Alexis Sanchez and Mesut Ozil, Oxlade-Chamberlain has entered the final year of his contract at Arsenal and supposedly rejected the chance to sign a lucrative extension worth a cool £180,000-a-week.
Chelsea were said to have failed with an initial £30m bid earlier in August, while Liverpool have also been mentioned heavily in connection with his signature over recent months.
The former Southampton prodigy has made 198 competitive appearances for Arsenal since arriving six years ago, yet it appears that he has become disillusioned with life in north London despite starting regularly in 2017. Oxlade-Chamberlain has mostly been deployed as a wing-back by Arsene Wenger in recent times and is believed to want to play more regularly in a more natural midfield position.
The incredibly versatile 24-year-old has played all but 28 minutes of Arsenal's season to date and featured for just over an hour of Sunday's embarrassing 4-0 defeat to Liverpool at Anfield. Wenger had previously stated his intention to keep a player whom he believes will become one of the most highly-rated in England over the coming years.
Oxlade-Chamberlain would follow Willy Caballero, Antonio Rudiger, Tiemoue Bakayoko and Alvaro Morata as Chelsea's fifth signing of the summer to date. Antonio Conte is targeting three new additions during the closing days of the window amid links to the likes of Leicester City midfielder Danny Drinkwater and Swansea City striker Fernando Llorente, although has been eager to stress that he remains committed to the club even in the event that further deals are not forthcoming.
In other Chelsea transfer news, Jeremie Boga has become the latest player to put pen to paper on a new contract before leaving on loan. The skillful 20-year-old Ivory Coast midfielder, who was handed his senior debut by Conte during the opening day defeat to Burnley after proving his worth on a pre-season tour of the Far East, penned a three-year deal before joining Harry Redknapp's Birmingham City for the rest of the season.
"Jeremie Boga has today signed a new three-year contract with Chelsea and will now join Birmingham City on loan for the rest of the 2017/18 season," Chelsea confirmed via their official website.
This will be academy graduate Boga's third temporary stint away from Stamford Bridge following respective spells with Rennes and Granada.