DePaula noted that Nike will have 10 business days to exercise the "match clause" option in their contract with Hayward.
On Saturday, A. Sherrod Blakely of NBC Sports Boston reported that Hayward was closing in on a multiyear agreement with Nike.
While Hayward has been a Nike athlete for much of his career, DePaula initially reported in August that Anta and New Balance were among the companies interested in signing him, along with Nike.
Anta is a Chinese company that has been in existence since 1994.
Hayward suffered major leg and ankle injuries in the first game of the 2017-18 season, causing him to miss the remainder of the campaign.
The 28-year-old signed with the Celtics last offseason after spending the first seven seasons of his career with the Utah Jazz.