Graham Potter is set to be appointed Chelsea manager in the next 24 hours, ending his three-year spell with Brighton.
Potter, 47, spoke to Chelsea owner Todd Boehly on Wednesday night after Thomas Tuchel was sacked and has reached a verbal agreement with the club.
Potter was at Brighton’s training ground on Thursday morning but did not lead the team’s session.
Chelsea hope to name a new manager before Saturday’s game away to Fulham.
The club, currently sixth in the Premier League, has also held talks with former Tottenham manager Mauricio Pochettino and Sporting Lisbon head coach Ruben Amorim about the vacant role.
Brighton are planning a press conference on Friday ahead of Saturday’s trip to Bournemouth, but it is not clear who will speak to the media.
Former Ostersunds FK and Swansea manager Potter led Brighton to a ninth-place finish last season, the club’s highest ever top-flight finish.
A former full-back in the Football League with Stoke, West Brom and York, Potter began his managerial career with Ostersunds FK in 2010, guiding them from the fourth tier of Swedish football to the first, winning the 2017 Swedish Cup and reaching the knockout stages of the Europa League.
He then took charge of Swansea City in June 2018, spending one season with the Championship side before joining Brighton following Chris Hughton’s dismissal.
Potter, who has been tipped as a future England boss, has led Brighton to fourth in the table this season after winning four, drawing one and losing one of their six Premier League games.
He was appointed in May 2019 and has taken the club to 15th, 16th as well as the ninth-place finish in his three seasons in charge.
With his brand of attacking and tactically-flexible football, Potter guided Ostersunds FK to three promotions in five seasons.
He took them to Sweden’s top division for the first time, followed by a first major trophy and a spot in the Europa League.
Former Borussia Dortmund and Paris St-Germain boss Tuchel was sacked despite bringing three trophies to Stamford Bridge in 20 months.
However, the team has lost three times already this season after the new owners spent £255.3m in the summer transfer window.
Johnny Cantor, Brighton commentator for BBC Radio Sussex
It is an interesting dynamic at Brighton and Hove Albion, as ordinarily when a coach departs, it follows a poor run or a major fall-out and a new manager would take over a struggling team.
Graham Potter led the Seagulls to their highest ever position in the top flight and their highest ever points total.
He would depart with the team fourth in the table. A tough act to follow.
However, he also arrived at a club with a plan and a strategy with excellent people already in place. That hasn’t changed.
Brighton are regarded as a forward-thinking, open-minded club with a highly successful owner who supports the cub.
Succession planning has been a key to their success over the last 15 years and that won’t change now.
It would undoubtedly be a blow to lose one of the best coaches in the country or possibly Europe, but any new face will have been considered carefully and have the right credentials and ethos to give them the best chance of further success.