Sam Allardyce has agreed to become Everton’s manager, six months after he stepped down at Crystal Palace saying he had “no ambitions to take another job”.

Allardyce is in line to become the permanent successor to Ronald Koeman after David Unsworth’s unsuccessful stint as caretaker. His first match will be at home to Huddersfield Town on Saturday. He has agreed an 18-month deal worth a reported £9m.

Timeline British managers never get a chance? Show Paul Lambert Aston Villa, replaced Alex McLeish Steve Clarke West Brom, replaced Roy Hodgson Nigel Adkins Reading, replaced Brian McDermott Mark Hughes Stoke, replaced Tony Pulis David Moyes Manchester United, replaced Alex Ferguson Tony Pulis Crystal Palace, replaced Ian Holloway Tim Sherwood Tottenham, replaced André Villas-Boas Garry Monk Swansea, replaced Michael Laudrup Neil Adams Norwich, replaced Chris Hughton Alan Irvine West Brom, replaced Pepe Mel Neil Warnock Crystal Palace, replaced Tony Pulis John Carver Newcastle, replaced Alan Pardew Alan Pardew Crystal Palace, replaced Neil Warnock Tony Pulis West Brom, replaced Alan Irvine Tim Sherwood Aston Villa, replaced Paul Lambert Chris Ramsey QPR, replaced Harry Redknapp Steve McClaren Newcastle, replaced John Carver Sam Allardyce Sunderland, replaced Dick Advocaat Mike Phelan Hull, replaced Steve Bruce David Moyes Sunderland, replaced Sam Allardyce Sam Allardyce Crystal Palace, replaced Alan Pardew Paul Clement Swansea, replaced Bob Bradley Craig Shakespeare Leicester, replaced Claudio Ranieri Roy Hodgson Crystal Palace, replaced Frank de Boer David Moyes West Ham, replaced Slaven Bilic Alan Pardew West Brom, replaced Tony Pulis

“Sam Allardyce will be at Finch Farm this afternoon to finalise terms on becoming the new manager of Everton,” read a club statement. “David Unsworth will remain in charge for tonight’s match against West Ham at Goodison Park.”

The 63-year-old is expected to attend the game and to be announced by the club on Thursday or Friday.

Farhad Moshiri, Everton’s majority shareholder, has been quoted on Twitter by Jim White of TalkSport as saying: “I really want to give him the support he needs. He can go as far as he wants. We need a strong leader, he gives us that.”

The former England manager shocked Palace by quitting on the grounds he wanted to travel and spend more time with his family. “I simply want to be able to enjoy all the things you cannot really enjoy with the 24/7 demands of managing any club, let alone one in the Premier League,” he said.

The former Leicester manager Craig Shakespeare and former Liverpool player and assistant Sammy Lee are expected to be part of the Allardyce ticket.

Allardyce, a former Bolton, Newcastle United, Blackburn and West Ham manager, has never been relegated from the top division and ensured Palace, last season, and Sunderland, the previous season, stayed up after he took over part-way through a campaign.

He held talks with Everton earlier this month but those broke down, with Allardyce saying the club “were hesitating that I was the man”.

Everton failed in attempts to take Marco Silva from Watford and were also linked with the Shakhtar Donetsk manager, Paulo Fonseca, and the Republic of Ireland’s Martin O’Neill.

Unsworth and Duncan Ferguson are both expected to be retained on the Everton staff.