NEW YORK (CNN/Money) - Nike Inc., the world's biggest maker of sports apparel, is close to signing an endorsement deal with tennis star Serena Williams worth at least $60 million, a news report said Monday.

Beaverton, Ore.-based Nike (NKE: Research, Estimates), in the midst of a rash of blockbuster athlete endorsement signings, is clearly looking beyond the insular tennis world to justify the Williams deal, which will be the largest female endorsement contract in history, people familiar with the deal told the SportsBusinessJournal.

YOUR E-MAIL ALERTS Nike Incorporated Serena Williams or Create your own Manage alerts | What is this?

The younger of the two Williams sisters will stop wearing attire from Puma, the German sneaker and apparel maker that signed her almost six years ago but never leveraged her stardom to create a major splash in tennis, the report said.

Three years ago, Nike lost out to Reebok, which signed Serena's older sister Venus to a $38 million, five-year deal, at the time the biggest for a woman athlete.

Serena, 22, had received $12 million over five years from Puma. That deal expired Jan. 15, and she wore Puma without a contract this year, the article said.

"Until we have a signed contract in hand, we have nothing to announce," a Nike spokesman told CNN/Money.

Officials at Puma were not immediately available for comment.