Andrews, 27, is undergoing a medical at Ewood Park prior to linking up with the former Dons boss Paul Ince for the second time.
Andrews was Ince's captain as the Dons won promotion from League Two as champions and secured the Johnstone's Paint Trophy last season.
However, his future at stadium:mk had been in doubt after he informed new manager Roberto Di Matteo of his desire to play at a higher level.
Andrews has been linked with a move Rovers since Ince replaced Mark Hughes in the managerial hot-seat earlier in the summer.
The Irish midfielder, who began his career with Wolves before moving to Milton Keynes in 2006, was also wanted by several Championship clubs.