Ashley Williams is expected to end his eight-year stint at Swansea City by joining Premier League rivals Everton.
John Stones' move from Goodison Park to Manchester City left a gap Wales and Swans captain Williams, 31, will fill in a move touted throughout the summer.
Ex-Wales defender Danny Gabbidon, a player consultant for Williams' agent, tweeted: "I believe a fee has been agreed between #EFC & #Swans for Ashley Williams.
"Medical booked and player en route."
More to follow.
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