That offer, expected to be in the region of £2million, looks to have been accepted with personal terms now just a mere formality with a three-year contract on offer for the powerful front-man.
Martinez signed Scotland two years ago for Swansea after being impressed with his performances for St Johnstone. In two seasons with the Welsh side he scored an impressive 53 goals in 105 matches.
What role he will play in Martinez's plans are unknown as the striker is untested in the Premiership and recently turned 30. However with only Hugo Rodallega and Marlon King as registered forwards on the books he will bring much needed competition to one of Wigan's least covered positions.