The Thunder posted their fourth straight win after Kevin Durant sank a pair of key foul shots in the closing minute.
Durant finished 8-of-8 from the line while scoring 22 points as the Thunder played their fourth game in five nights.
Marc Gasol led the Grizzlies with 20 points, 14 rebounds and four blocks. Mike Conley's 15 points and 10 assists for Memphis, which has lost three straight games.
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