SOUTHLAKE — Southlake Carroll spent most of Friday night on a slow grind for that one opportunity to put away Justin Northwest.So when Dragons guard Sammy Silver buried a key 3-pointer late and teammate Cooper Osburn came up with a big steal in the waning moments, it was fitting that the Texans ended the game with a huge defensive play. Northwest’s David Ogunwolu swatted away a driving Carroll layup as the buzzer sounded, sealing a 51-50 road win in District 4-5A. The victory helped cement a playoff spot for Northwest (20-5 overall, 7-2 district) and perhaps also a run at the district title. Carroll (10-8, 4-5) is currently in fifth place.“It was crazy,” Ogunwolu said. “Everything we did there at the end and then Coach switched us to a zone to try and push that final shot to the outside. I had a good angle on the drive and there wasn’t any doubt I was going to block it.”Northwest avoided losing for the third time in four district games.The Texans led 51-44 with 1:22 to go before Carroll clawed to within four. That’s when Silver knocked down a 3-pointer to pull the Dragons within 51-50. Carroll chose not to foul, and Osburn came up with the big steal to give Carroll life with 18.7 seconds remaining. “They played us tough,” Northwest coach Mike Hatch said. “We did a lot of things to blow that game, but when we needed the big play, we got it from the guy I feel like is the best defensive player in our district.”Elijah Christman led Northwest with 15 points and Johnson had 14. Humphrey had 13 for Carroll and Silver had 11.