The Golden State Warriors, San Antonio Spurs and incumbent Oklahoma City Thunder are the first three known teams to secure face-to-face meetings with free agent-to-be Kevin Durant, starting next weekend, according to league sources.

Sources told ESPN that the list of teams that get to pitch Durant directly will grow before NBA free agency officially begins July 1 at 12:01 a.m. ET, but the list of confirmed suitors for now features the Thunder and their two main rivals in the Western Conference.

The Warriors and Spurs, sources say, are both planning to load a plane full of key organizational figures -- including Stephen Curry and Klay Thompson for Golden State and Gregg Popovich and Tim Duncan for San Antonio -- to fly to an undisclosed location once free-agency season starts to try to lure Durant away from the only franchise he has ever played for.

More teams are expected to get the chance to try to lure Kevin Durant after free agency begins, sources say. Layne Murdoch/NBA/Getty Images

Expected to sit alongside Durant at the forthcoming meetings, sources say, is his agent Rich Kleiman and selected family members and friends.

After Oklahoma City lost to Golden State in the Western Conference finals, ESPN reported that the most likely scenario for Durant this summer was staying with the Thunder on a two-year deal that includes a player option after Year 1 that would allow him to return to free agency in July 2017 alongside teammate Russell Westbrook.

But the Warriors, sources say, increasingly believe their chances of persuading Durant to leave the Thunder after a successful nine-season run were enhanced significantly by the fact that Golden State lost the NBA Finals to Cleveland in seven games despite taking a 3-1 series lead.

The Warriors would have to relinquish a number of looming free agents, including Harrison Barnes and Festus Ezeli, and at least one more significant contract -- such as Andrew Bogut or Andre Iguodala -- to create sufficient salary-cap space to sign Durant. But as ESPN reported earlier this week, Golden State is "all-in" on a Durant pursuit.

"All I can say is I will be very aggressive," Warriors owner Joe Lacob vowed on his way out of Oracle Arena after Game 7.

Other teams hopeful of getting an opportunity to make a recruiting pitch to 2016's most coveted free agent but whose status is not yet known include the Miami Heat, Boston Celtics, Los Angeles Clippers, New York Knicks and Los Angeles Lakers.

The Houston Rockets have long planned to chase Durant in free agency, but when Durant and Rockets star James Harden were spotted spending time together earlier this month, sources said the Rockets are not expected to get serious consideration as a destination from Durant.

Sources say Durant's hometown Washington Wizards are likewise pessimistic about their chances of emerging as a real factor in the Durant sweepstakes, despite the recent hiring of former Thunder coach Scott Brooks.