Russell Westbrook has agreed to sign a five-year, $205 million extension with the Oklahoma City Thunder, according to ESPN's Adrian Wojnarowski. This contract will make the biggest total amount in NBA history — amassing six years and $233.5 million.

Through Westbrook's agent Thad Foucher and general manager Sam Presti have signed the deal and delivered it to the league office, expected to be made official later today.

The deal will kick in starting the 2018-19 season, also making him the richest salaried American athlete, making an average of 41 million per year once his new contract starts next season.

Westbrook made use of the Designated Player Veteran Extension, or “supermax” deal, which allowed the reigning Most Valuable Player to garner 35 percent of the salary cap and five extra seasons. His new salary will start at $35.3 million for the first year, increasing every season.

The 6-foot-3 point guard is coming off a season for the ages, averaging a triple-double of 31.6 points, 10.7 rebounds, 10.4 assists, and 1.6 steals per game.

Westbrook released a statement (via ESPN's Royce Young) following the signing along with an Instagram photo of himself captioned with his signature phrase: “Why not?”

“I've said it before, and I'll say it again, there is no place I would rather be than Oklahoma City,” said Westbrook. “I am so honored to have the opportunity to continue my career here with the Thunder. From day one the support that Mr. Bennett, Sam, Troy and the entire organization have given me and my family has been incredible, and we are so grateful. When you play in Oklahoma City you play in front of the best fans in the world, I'm looking forward to bringing everything I've got, for them, this city and for this organization. WHY NOT?”

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This signing provides Oklahoma City with the much-needed security they sought out during this summer, putting the offer on the table the very first day of free agency in hopes their prized cornerstone player won't become another offseason loss like Kevin Durant was in 2016.

The deal also comes around at a peculiar date in time, given today is his Durant's birthday, as noted by Young.

The Thunder kept true to their promise to make him the centerpiece of the franchise, surrounding him with the All-Star talents of Paul George prior to the start of the free agent market and delivering Carmelo Anthony just before the start of training camp — crafting a three-headed monster that can match the heavy firepower of this star-studded Western Conference.

This summer could also signify not only the best offseason the franchise has ever had, but Presti having a leg up on the competition in the race for Executive of the Year, snagging two All-Star caliber players and re-signing an MVP during this shortened offseason.

Westbrook is also coming off what's expected to be the richest shoe deal in NBA history after inking a 10-year deal with Jordan Brand earlier this summer.