Prior to hammering out his new deal with the Heat, Winslow could've become a restricted free agent following the 2018-19 season. Wojnarowski noted the two sides had until Monday to finalize the extension.
The Athletic's Shams Charania reported the third year of the deal is a team option.
The fact Miami would give Winslow a new contract now could be instructive regarding the team's other priorities.
The Miami Herald's Anthony Chiang and Barry Jackson reported in September that Winslow could be among the Heat players included in a trade for Jimmy Butler.
According to Wojnarowski, Miami and the Minnesota Timberwolves had discussed a deal that involved Josh Richardson going to the Timberwolves. The Heat backed away when Minnesota "pushed late for a sweeter return."
Whether he would've been part of the Butler package or not, trading Winslow is more difficult now.
Bobby Marks @BobbyMarks42
The rookie extension for Justise Winslow now comes with the poison pill provision. Although Winslow can still be traded, the restriction makes it extremely difficult during the 2018-19 season. For trade purposes, the Winslow salary would count as $10.6M... https://t.co/4P9tzO61iL
Considering both his performance and the Heat's payroll, the fact Miami would offer Winslow $13 million annually is somewhat surprising.
Winslow's shooting offered a lot of encouragement. After hitting just 25.8 percent of his three-pointers through his first two years, he was a 38.0 percent shooter from beyond the arc in 2017-18. By improving as a shooter, Winslow becomes a more versatile forward, capable of lining up as a small-ball stretch 4.
Miami is taking a leap of faith with the 2015 first-round pick to some extent. Just once in three years has he appeared in at least 70 games, and one good year doesn't entirely erase what had been an underwhelming start to his career.
But Winslow's extension essentially amounts to a two-year commitment if things don't work out, which won't put a serious strain on the Heat financially.
The terms also work out well for Winslow, who can return to free agency when he's 24 or 25.