Martin Brodeur couldn’t start and late replacement Johan Hedberg couldn’t stop the Devils’ slide. After Brodeur pulled himself out of a scheduled start during pregame warm-ups because of a sore back, the Devils turned in another lackluster effort in a 4-2 loss to the Winnipeg Jets on Sunday at Prudential Center. The Devils have won just two of their past seven games (2-4-1) since surging to the top of the Eastern Conference standings with a five-game winning streak. Their inconsistent play over the past two weeks would seem to be their bigger concern because both Brodeur and coach Pete DeBoer insisted that Brodeur’s sore back is not a serious problem. “From everything I’m told, I’m not concerned,” DeBoer said. “Everything should be fine,” Brodeur said. “I don’t think it’s a big deal. I don’t think anybody around here is worried about it.” Then again, Brodeur and DeBoer both thought the future Hall of Famer would be OK to play Sunday. And Brodeur is 40 years old and missed time each of the past two seasons because of injuries. Last season, he missed six games in October with a right shoulder injury. In 2010-11, Brodeur missed 10 games — over two layoffs — because of a bruised right elbow and an additional four games with a sprained MCL in his right knee.