James Harden and Russell Westbrook could be in line for new deals. (AP)

The National Basketball Association’s new Collective Bargaining Agreement includes a special provision that grandfathers Houston’s James Harden and Oklahoma City’s Russell Westbrook into the windfall of super-max contract extensions available to several star players this summer, league sources told The Vertical.

This summer, Westbrook could sign a five-year, $219 million contract extension that would begin in the 2018-19 season. He’ll make $28.5 million in 2017-18.

Harden could sign for an additional four years and $171 million starting in 2019 – on top of the $58.7 million owed to him in the next two years of his current contract.

Westbrook and Harden are two of the NBA’s top Most Valuable Player candidates and could join a class of Steph Curry, Blake Griffin, Paul George and DeMarcus Cousins that is eligible to earn extensions starting at $36 million a season.

The NBA and Players Association negotiated the addendum to the new Designated Player Veteran Exception to grant Harden and Westbrook 2017 eligibility despite both signing contract extensions in the summer of 2016. Under normal CBA rules, players aren’t allowed to sign extensions in consecutive years.

The league and union worked together on the Harden/Westbrook arrangement with the belief that neither player, nor the Rockets or Thunder, should be punished for honoring the spirit of the rules: encouraging players to remain with current teams on contract extensions. When those deals were negotiated to raise the players’ salaries and add extra years to the contracts, the teams and players were unaware that the new CBA would offer such substantial financial rewards for waiting another year.

The NBA’s Board of Governors and the Players Association will vote on ratifying the seven-year CBA this week, league sources told The Vertical. The owners and players have been provided with deal-point memos to study the agreements, and both sides are expected to approve the CBA.

In the aftermath of Kevin Durant’s free-agent departure to Golden State, the NBA is trying to financially motivate players to remain with existing teams. With the new Designed Player Veteran Exception, stars meeting a set of predetermined standards can be paid as much as 35 percent of a team’s salary cap. Those standards include inclusion on one of the three All-NBA teams, or winning the MVP or Defensive Player of the Year awards.

Before the summer renegotiation, Westbrook would’ve been eligible for the new exception in 2017 under the league’s new guidelines, although Harden would need to minimally make one of the All-NBA teams this season to be eligible. Harden wasn’t selected to an All-NBA team in 2015-16, and players need to make an All-NBA team in two of the previous three years to be eligible for the substantial raise.

If Westbrook were to sign the five-year extension this summer, he would play the 2017-18 season for the $28.5 million under the current deal and the five additional years would start in 2018-19.

Harden could sign the extension this summer, with the new terms at $36 million-plus kicking in for four additional years beginning in 2019.

For now, it is less likely that Harden might consider the extension this summer than Westbrook, league sources told The Vertical. Harden might prefer to wait until closer to his free agency and continue to evaluate the Rockets’ ability to develop into a championship contender, sources told The Vertical. Harden has a massive adidas shoe deal that guarantees him great earning power beyond his NBA contract. What’s more, the Rockets are under no obligation to offer him the extension this summer.

Harden signed a four-year, $118 million renegotiation in July. The deal includes a player option for the 2019-20 season, which would allow him to return to unrestricted free agency in the summer of 2019. Another reason Harden needed a waiver in the new CBA, sources told The Vertical: because he will be entering his 10th year – and the Designed Player Veteran Exception rule covers players entering their eighth or ninth years of service.

Westbrook – who signed a three-year, $85.7 million renegotiation – is owed $28.5 million in 2017-18 and has a player option for $30 million in 2018-19.

Front-Office Insider Bobby Marks contributed to this report.

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