Deron Williams exploded for 50 points on Tuesday in Istanbul and Besiktas Milangaz needed every one of them in a 105-94 EuroChallenge victory over BG Göttingen.
The point guard, one of the first NBA players to move to Europe during the NBA lockout, made 17 of his 23 shots from the floor.
Included in that were seven of 10 makes from three-point range.
Göttingen, who have been struggling this season, trailed 91-90 after their 23-year-old point guard Louis Dale buried a shot from the arc with 2:14 to go.
Williams went to the other end, though, and with the 24-shot clock winding down answered with a three-pointer.
Then with Besiktas on top 95-90 and 1:10 remaining, Williams struck again from the arc before going in for a lay-up on his team's next possession for a 100-90 lead.
The USA Olympic gold medal winner reached the 50-point plateau with a lay-up on a fast-break just 13 seconds from the end.
The most points ever scored by Williams in the NBA came in a 2010 when he played for Utah against Oklahoma City and poured in 42.
David Hawkins finished with 23 points for Besiktas, who improved to 3-0 in Group B.
Raymond Sykes led the Violets with 25 points and Kyle Bailey had 19.
The German club fell to 0-3 with the defeat.