McGregor, 36, is expected to complete a deal to return to his old club within the next 24 hours.
The Scottish international looks set to leave Hull City after five years. The Championship club stalled on the offer of a new contract earlier this season and will now likely see their first-choice goalkeeper leave this summer.
Arfield looks set to seal his move to Ibrox on a pre-contract by the end of the week.
He will see his current deal with Sean Dyche’s Premier League outfit expire in two months.
The former Falkirk star will sign a three-year contract with Rangers and return to the Scottish top flight eight years after leaving for Huddersfield.