When the Oklahoma City Thunder finally decided to turn it on, the Phoenix Suns didn’t stand a chance. By the time the Thunder did, the only question was what took so long? A dominant second half powered the Thunder to a 127-96 win over the Suns on Friday night inside Chesapeake Energy Arena. OKC scored a season-high 72 second-half points and pulled away using a 36-20 third quarter. The Thunder led by as many as 32 points and saw all 13 active players score. “Offensively, it goes without saying,” said Thunder coach Scott Brooks. “We were clicking on all cylinders.” Friday’s point total was the most the Thunder has scored all year. The previous best was 124 against Houston on Dec. 29. Kevin Durant led five players in double figure scoring with 21 points. Thabo Sefolosha scored 18, making four of six 3-pointers. Russell Westbrook and Kendrick Perkins added 17 points each — the most Perkins has scored in a Thunder uniform — and Kevin Martin had 16 points off the bench. The Thunder shot 57.5 percent, dished 29 assists for the second straight game and had just eight turnovers. OKC also connected on 14 of 21 3-pointers, one shy of matching a season high for makes. “That was one of the few times where you can really say offensively we won the game,” Brooks said.