Newcastle boss Steve Bruce hopes to sign Joe Willock on a six-year deal by 12:00 BST so he can play against West Ham on Sunday.
The Arsenal midfielder, 21, completed a medical on Friday morning and Bruce said he would train before assessing whether he would feature in Newcastle’s game at St James’ Park.
The deal is in excess of £20m after a successful loan spell last season.
“We had to be patient but it was worth the wait,” Bruce said.
“Where else can you find a 21-year-old who scored seven on the trot [on loan last season] and plays like him? Fair play to everyone to get it done.”
England under-21 international Willock scored eight goals for Newcastle while on loan in the second half of last season, including seven in consecutive games, to help steer the club away from the relegation zone.
Bruce admitted that at one point he “did not think the deal would happen” after Arsenal turned down a loan approach.
But he said that a permanent deal “was great for us” and would improve the team as they seek to better last season’s 12th-placed finish in the Premier League.
“The big thing for us is to try and improve on last year,” Bruce added.
“We had a good start and a good finish, but an awful winter time. We need to be lucky with injuries and certainly with Joe in team we looked a threat and to score those goals he gave us something different and he improves us.
“Little by little we try to improve.”