Ince is one of the Championship's hottest properties, having scored 18 goals for the Seasiders last season.
Mackay said at a press conference on Thursday: "We've had a bid accepted by Blackpool and agreed terms with his agent.
"Tom and his dad were both on holiday so Monday was the earliest time we could have a chat.
"Friday morning we'll have a decision one way or another."
- Paul Ince