Red Bull sports boss Oliver Mintzlaff has criticized Mercedes team principal Toto Wolff for his constant courting of Formula One world champion Max Verstappen. Mercedes are losing Lewis Hamilton to Ferrari next year and have watched Verstappen dominate the sport for the last three seasons. A power struggle at Red Bull may open the door for the Dutchman to one day decide to leave, but Mintzlaff has warned Wolff off. “I understand the pressure that Toto Wolff and perhaps other teams are under after years of being left behind. But I think that Toto Wolff should concentrate on his own challenges. …