World No.1 Jason Day is reportedly set to sign a lucrative deal with sporting giants Nike, according to ESPN.

Day is set to sign a deal worthย $US10 million ($AU 13.4 million) annually to wear Nike apparel.

The Australian has spent the past 25 weeks at No.1, the most weeks in the top spot since Rory Mcllroy from August 2014 and August 2015.