Coles Group's fierce price cutting counter attack in the past year seems to have resulted in Woolworths' CEO Michael Luscombe retiring.

The news, which didn't come as a surprise to the market with the change tipped in two media reports yesterday, was conveyed in a statement to the ASX.

Mr Lucombe will retire at the end of September after five years as CEO and will be replaced by Grant O'Brien, a man unknown to the market who has been Woolies chief operating officer for food and petrol.

The company's shares rose after the news, hitting a day's high of $27.32, before retracing to end down 19c