On Saturday, Karen Guregian of the Boston Herald provided excepts from an interview Brady did with Oprah Winfrey, which is set to air Sunday on OWN.
"I think about [retiring] more now than I used to," he said. "I think I'm seeing there's definitely an end coming sooner, rather than later."
Brady didn't provide a firm timetable for his departure from the NFL, however, only telling Oprah he'll continue to play "as long as I'm still loving it."
The 40-year-old California native is already in the conversation about the greatest player in NFL history thanks to a resume that includes five Super Bowl championships, three MVP awards and 13 Pro Bowl selections to go with numerous other accolades.
His comments about potentially heading toward retirement represent a possible change of heart, though.
In May 2017, Brady told Ian O'Connor of ESPN.com he wanted to play at least until his "mid-40s" and wouldn't rule out trying to play at 50.
"If you said 50, then you can say 60, too, then 70," he said. "I think 45 is a pretty good number for right now. I know the effort it takes to be 40. ... My love for the sport will never go away. I don't think at 45 it will go away."
Brady is under contract with the Patriots through the 2019 season.
New England is set to open the 2018 campaign Sept. 9 against the Houston Texans. It will mark the superstar QB's 19th year in the NFL.