DALLAS—Luka Doncic went to the bench with five fouls just 53 seconds into the third quarter. Dallas’ second-best point guard joined him a little bit later for the same reason. The Mavericks never lost the lead against Trae Young and Atlanta, beating the Hawks 103–94 on Sunday night. Doncic had another triple-double—18 points, 10 rebounds and 11 assists—and Jalen Brunson scored 22 points despite sitting for long stretches because of the fouls. “I’m all about teaching,” said Dallas coach Jason Kidd, who chose not to pull Doncic after the superstar picked up his third foul with 2:50 left in the first half. The Mavericks used a patchwork lineup that looked similar to when the team was battling COVID-19 issues earlier in the season. “There’s a bigger picture,” he added. “It can happen in the playoffs, it can happen in Game 7. Everybody has to be ready. There’s no guarantee Luka’s …