Butler hit a game-tying three-pointer with no time remaining in regulation, West hit the winning jumper with 8.8 seconds left in overtime, and the Hornets stunned the host Miami Heat, 93-87, on Tuesday night.
Chris Paul finished with 26 points, nine rebounds and nine assists, and Peja Stojakovic added 24 points for the Hornets (48-29), who not only clinched their postseason berth but also stayed thickly in the hunt for home-court advantage in the first round of the Western Conference playoffs.
"To clinch a second straight playoff is a good feeling for our guys, and we're going to take it," New Orleans coach Byron Scott said. "I congratulated them in the locker room. Even though it's not our main goal, it's still one of our goals."
Dwyane Wade scored 32 points before getting ejected with 1.4 seconds remaining, and Michael Beasley added 25 for Miami (41-37), which remained a half game ahead of Philadelphia in the race for the No. 5 spot in the East playoffs. The Heat fell three games behind Atlanta for the fourth seed.
"We just have to keep on plugging away," Heat coach Erik Spoelstra said. "We've had some very difficult losses the last three weeks. We've bounced back from these kind of losses and we need to continue to do so."
Bobcats 101, 76ers 98: : Gerald Wallace scored 29 points, including the final four of the game, and host Charlotte (35-43) ended a three-game losing streak. Philadelphia (40-37) overcame one of its poorest starts only to falter down the stretch.
Spurs 99, Thunder 89: : Tim Duncan had 25 points and 15 rebounds, and Drew Gooden provided a needed lift off the bench as visiting San Antonio (50-27) won its first game since learning Manu Ginobili would miss the rest of the season. The Spurs pulled away after Oklahoma City (21-56) closed within one early in the fourth quarter.
Trail Blazers 96, Grizzlies 93: : Travis Outlaw banked in a 14-footer with 13 seconds left as visiting Portland (49-28) got its fifth victory in six games. Memphis (22-55) ended a four-game winning streak.
Rockets 93, Magic 83: : Yao Ming had 20 points and 16 rebounds as host Houston (50-28) stayed a half game behind San Antonio in the Southwest Division. Orlando (57-20) slipped one game behind second-place Boston in the Eastern Conference standings.
Bulls 110, Knicks 103: : Kirk Hinrich scored 25 points to lead five players in double figures for host Chicago (38-40). Wilson Chandler scored 26 points to lead the Knicks (30-48).