Kevin Durant and Russell Westbrook are no longer teammates.
Why did Durant elect to go in a new direction?
"Ultimately he got frustrated and felt that they (Thunder) had plateaued," a source told Howard Beck of Bleacher Report. "[Billy Donovan] came in, and he (Durant) still had the same issues that he had with Russ under Scotty (Brooks).
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[POOLE: Analysis: Durant's impact for Warriors outweigh any negatives]
"The offense didn't change much. He still had to take a ton of contested shots every game; and that's when he had the ball at all."
Last year, Durant averaged 28.2 points on 19.2 field goal attempts per game. He shot 50.5 percent from the field and 38.7 percent from deep.
Westbrook averaged 23.5 points and 10.4 assists on 18.1 shots per game. He shot 45.4 percent overall, and 29.6 percent from beyond the arc.
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The Thunder were second in the league in points per game (110.2) and offensive rating (109.9).
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But Oklahoma City was 10th in assists per game (23.0) and 22nd in assist percentage.
The Warriors led the league in points (114.9), offensive rating (112.5), assists (28.9) and assist percentage (68).
"He's never going to have a game in Golden State where Steve Kerr has to say at halftime, 'You guys need to get Kevin the ball,' which happened in OKC," the same source told Beck.
In his announcement on The Players' Tribune on Monday, Durant explained why he would sign with the Warriors.
"The primary mandate I had for myself in making this decision was to have it based on the potential for my growth as a player — as that has always steered me in the right direction. But I am also at a point in my life where it is of equal importance to find an opportunity that encourages my evolution as a man: moving out of my comfort zone to a new city and community which offers the greatest potential for my contribution and personal growth.
"With this in mind, I have decided that I am going to join the Golden State Warriors."