Everton said in a statement: "Sam Allardyce will be at USM Finch Farm this afternoon to finalise terms on becoming the new manager of Everton Football Club.

"David Unsworth will remain in charge of the Blues for tonight's Premier League match against West Ham United at Goodison Park."

Former England boss Allardyce ruled himself out of the running earlier this month, claiming he did not feel the Toffees were convinced he was the right man.

But, after Everton's pursuit of Watford boss Marco Silva was met with a firm rebuttal from Vicarage Road, the club returned to Allardyce.

This will be the 10th English club managerial position of the 63-year-old's career, with Allardyce most recently having guided Crystal Palace to safety last season.

When he left Selhurst Park in May, Allardyce said he had "no ambitions" to take another managerial job.

But the chance to turn around Everton's faltering ship has lured him back, and Allardyce is expected to have a watching brief at Goodison Park on Wednesday night.

Everton are currently sitting 17th in the table, two points ahead of the Hammers.

David Unsworth has been in temporary charge since Ronald Koeman was sacked on October 23 and the under-23s boss had made clear his desire to take on the job permanently.

But his seven-game tenure has been little short of disastrous, with Everton losing five games and winning just one.

That victory, when the Toffees came from two down late on to secure a 3-2 victory over Watford, looked like it might be a turning point.

But they have lost their last two matches 5-1 to Atalanta and 4-1 against Southampton, taking the tally of goals Everton have conceded this season in all competitions to 46.

The club's prospects had appeared so different at the beginning of the season with Everton having invested heavily following last season's impressive seventh-place finish.

After years of being unable to come close to matching the financial clout of the Premier League's big guns, Everton finally had significant backing thanks to new owner Farhad Moshiri.

But, after taking four points from their first two games, Everton managed the same tally from their next seven fixtures and Koeman was sacked.

Everton's chief problem is clear to see. They have conceded more than twice as many goals as they have scored having failed to replace leading scorer Romelu Lukaku following his summer departure for Manchester United.

The Toffees hierarchy will feel they have gone for a safe pair of hands, with Allardyce having taken over both Palace and Sunderland in graver situations and led them to safety.

His achievements at the Stadium of Light - which look all the more impressive given what has happened since - earned him his dream job with England.

But that turned sour after only one match, with Allardyce stepping down in September 2016 following a newspaper sting.