SOUTHLAKE — Gretchen Morrison nailed seven 3-pointers on her way to a game-high 31 points as Southlake Carroll’s perimeter game wore down Justin Northwest, 77-37 on Friday night at Southlake Carroll.The win keeps the Dragons (24-4, 11-0) perfect in District 4-5A play and solidified their position as a team to watch with the playoffs beginning in just over two weeks. Carroll clinched a playoff spot with the win. “Gretchen was firing away tonight,” Carroll coach Teri Morrison said. “That’s nice to have when you’re missing part of your inside game, and it’s good that we have that balance.”Sophomore post Anna Hurlburt, averaging 8.8 points per game this season, didn’t play Friday because of an injury. She’s expected to return Tuesday at Keller.Carroll’s hole in the middle wasn’t a factor, though, as Morrison was unstoppable from long range.It was an overwhelming performance against Northwest (12-12, 4-7), a team battling for the district’s final playoff spot. Even with the loss, the Texans share fourth place with Keller Fossil Ridge (8-18, 4-7), which beat Keller Central 36-38 on Friday. Carroll started the rout early, going 11 for 17 from the floor in the second quarter and building a 40-20 halftime lead. Morrison led the charge in the first quarter, making three shots from beyond the 3-point arc. She added two more in the second quarter. She and Kennedy Leonard helped fuel a 22-7 run with that second-quarter effort. Leonard hit a pair of 3-pointers as she scored 11 of her 13 points in the second quarter.Brianna Barnhill had 15 points to pace Northwest and Alexus Brigham and Bailey Porter each added nine.